Inhibitors of interleukin-1β converting enzyme

ABSTRACT

The present invention relates to novel classes of compounds which are inhibitors of interleukin-1β converting enzyme. The ICE inhibitors of this invention are characterized by specific structural and physicochemical features. This invention also relates to pharmaceutical compositions comprising these compounds. The compounds and pharmaceutical compositions of this invention are particularly well suited for inhibiting ICE activity and consequently, may be advantageously used as agents against interleukin-1 mediated diseases, including inflammatory diseases, autoimmune diseases and neurodegenerative diseases. This invention also relates to methods for inhibiting ICE activity and methods for treating interleukin-1 mediated diseases using the compounds and compositions of this invention.

This is a division of application Ser. No. 08/440,898, filed May 25,1995 entitled Inhibitors of Interleukin-1β Converting Enzyme, now U.S.Pat. No. 5,656,627; which is a continuation-in-part of application Ser.No. 08/261,452 filed on Jun. 17, 1994 entitled Inhibitors ofInterleukin-1β Converting Enzyme, now U.S. Pat. No. 5,756,466.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to novel classes of compounds which areinhibitors of interleukin-1β converting enzyme ("ICE"). The ICEinhibitors of this invention are characterized by specific structuraland physicochemical features. This invention also relates topharmaceutical compositions comprising these compounds. The compoundsand pharmaceutical compositions of this invention are particularly wellsuited for inhibiting ICE activity and consequently, may beadvantageously used as agents against interleukin-1 ("IL-1") mediateddiseases, including inflammatory diseases, autoimmune diseases andneurodegenerative diseases. This invention also relates to methods forinhibiting ICE activity and methods for treating interleukin-1 mediateddiseases using the compounds and compositions of this invention.

BACKGROUND OF THE INVENTION

Interleukin 1 ("IL-1") is a major pro-inflammatory and immunoregulatoryprotein that stimulates fibroblast differentiation and proliferation,the production of prostaglandins, collagenase and phospholipase bysynovial cells and chondrocytes, basophil and eosinophil degranulationand neutrophil activation. Oppenheim, J. H. et al, Immunology Today, 7,pp. 45-56 (1986). As such, it is involved in the pathogenesis of chronicand acute inflammatory and autoimmune diseases. IL-1 is predominantlyproduced by peripheral blood monocytes as part of the inflammatoryresponse and exists in two distinct agonist forms, IL-1α and IL-1β.Mosely, B. S. et al., Proc. Nat. Acad. Sci., 84, pp. 4572-4576 (1987);Lonnemann, G. et al., Eur.J. Immunol., 19, pp. 1531-1536 (1989).

IL-1β is synthesized as a biologically inactive precursor, pIL-1β.pIL-1β lacks a conventional leader sequence and is not processed by asignal peptidase. March, C. J., Nature, 315, pp. 641-647 (1985).Instead, pIL-1β is cleaved by interleukin-1β converting enzyme ("ICE")between Asp-116 and Ala-117 to produce the biologically activeC-terminal fragment found in human serum and synovial fluid. Sleath, P.R., et al., J. Biol. Chem., 265, pp. 14526-14528 (1992); A. D. Howard etal., J. Immunol., 147, pp. 2964-2969 (1991). Processing by ICE is alsonecessary for the transport of mature IL-1β through the cell membrane.

ICE is a cysteine protease localized primarily in monocytes. It convertsprecursor IL-1β to the mature form. Black, R. A. et al., FEBS Lett.,247, pp. 386-390 (1989); Kostura, M. J. et al., Proc. Natl. Acad. Sci.USA, 86, pp. 5227-5231 (1989). ICE, or its homologues, also appears tobe involved in the regulation of cell death or apoptosis. Yuan, J. etal., Cell, 75, pp. 641-652 (1993); Miura, M. et al., Cell, 75, pp.653-660 (1993); Nett-Fiordalisi, M. A. et al., J. Cell Biochem., 17B, p.117 (1993). In particular, ICE or ICE homologues are thought to beassociated with the regulation of apoptosis in neurogenerative diseases,such as Alzheimer's and Parkinson's disease. Marx, J. and M. Baringa,Science, 259, pp. 760-762 (1993); Gagliardini, V. et al., Science, 263,pp. 826-828 (1994).

ICE has been previously described as a heterodimer composed of twosubunits, p20 and p10 (20 kDa and 10 kDa molecular weight,respectively). These subunits are derived from a 45 kDa proenzyme (p45)by way of a p30 form, through an activation mechanism that isautocatalytic. Thornberry, N. A. et al., Nature, 356, pp. 768-774(1992). The ICE proenzyme has been divided into several functionaldomains: a prodomain (p14), a p22/20 subunit, a polypeptide linker and ap10 subunit. Thornberry et al., supra; Casano et al., Genomics, 20, pp.474-481 (1994).

Full length p45 has been characterized by its cDNA and amino acidsequences. PCT patent applications WO 91/15577 and WO 94/00154. The p20and p10 cDNA and amino acid sequences are also known. Thornberry et al.,supra. Murine and rat ICE have also been sequenced and cloned. They havehigh amino acid and nucleic acid sequence homology to human ICE. Miller,D. K. et al., Ann. N.Y. Acad. Sci., 696, pp. 133-148 (1993); Molineaux,S. M. et al., Proc. Nat. Acad. Sci., 90, pp. 1809-1813 (1993). Knowledgeof the primary structure of ICE, however, does not allow prediction ofits tertiary structure. Nor does it afford an understanding of thestructural, conformational and chemical interactions of ICE and itssubstrate pIL-1β or other substrates or inhibitors.

ICE inhibitors represent a class of compounds useful for the control ofinflammation or apoptosis or both. Peptide and peptidyl inhibitors ofICE have been described. PCT patent applications WO 91/15577; WO93/05071; WO 93/09135; WO 93/14777 and WO 93/16710; and European patentapplication 0 547 699. However, due to their peptidic nature, suchinhibitors are typically characterized by undesirable pharmacologicproperties, such as poor oral absorption, poor stability and rapidmetabolism. Plattner, J. J. and D. W. Norbeck, in Drug DiscoveryTechnologies, C. R. Clark and W. H. Moos, Eds. (Ellis Horwood,Chichester, England, 1990), pp. 92-126. This has hampered theirdevelopment into effective drugs.

Accordingly, the need exists for compounds that can effectively inhibitthe action of ICE, for use as agents for preventing and treating chronicand acute forms of IL-1 mediated diseases, including various cancers, aswell as inflammatory, autoimmune or neurodegenerative diseases.

SUMMARY OF THE INVENTION

The present invention provides novel classes of compounds, andpharmaceutically acceptable derivatives thereof, that are useful asinhibitors of ICE. These compounds can be used alone or in combinationwith other therapeutic or prophylactic agents, such as antibiotics,immunomodulators or other anti-inflammatory agents, for the treatment orprophylaxis of diseases mediated by IL-1. According to a preferredembodiment, the compounds of this invention are capable of binding tothe active site of ICE and inhibiting the activity of that enzyme.

It is a principal object of this invention to provide novel classes ofinhibitors of ICE. These novel classes of ICE inhibitors arecharacterized by the following structural and physicochemical features:

a) a first and a second hydrogen bonding moiety, each of said moietiesbeing capable of forming a hydrogen bond with a different backbone atomof ICE, said backbone atom being selected from the group consisting ofthe carbonyl oxygen of Arg-341, the amide --NH-- group of Arg-341, thecarbonyl oxygen of Ser-339 and the amide --NH-- group of Ser-339;

b) a first and a second moderately hydrophobic moiety, said moietieseach being capable of associating with a separate binding pocket of ICEwhen the inhibitor is bound thereto, said binding pocket being selectedfrom the group consisting of the P2 binding pocket, the P3 bindingpocket, the P4 binding pocket and the P' binding pocket; and

c) an electronegative moiety comprising one or more electronegativeatoms, said atoms being attached to the same atom or to adjacent atomsin the moiety and said moiety being capable of forming one or morehydrogen bonds or salt bridges with residues in the P1 binding pocket ofICE.

It is also an object of this invention to provide a method foridentification, design or prediction of ICE inhibitors comprising thesteps of:

a) selecting a candidate compound of defined chemical structurecomprising at least two hydrogen bonding moieties, at least twomoderately hydrophobic moieties and one electronegative moietycomprising one or more electronegative atoms attached either to the sameatom or to adjacent atoms in the electronegative moiety;

b) determining a low-energy conformation for binding of said compound tothe active site of ICE;

c) evaluating the capability of said compound in said conformation toform at least two hydrogen bonds with the non-carbon backbone atoms ofArg-341 and Ser-339 of ICE;

d) evaluating the capability of said compound in said conformation toassociate with at least two of the binding pockets of ICE selected fromthe group consisting of the P2 binding pocket, the P3 binding pocket,the P4 binding pocket and the P' binding pocket;

e) evaluating the capability of said compound in said conformation tointeract with the P1 binding pocket of ICE; and

f) accepting or rejecting said candidate compound as an ICE inhibitorbased on the determinations and evaluations carried out in the precedingsteps.

It is a further object of this invention to provide novel classes of ICEinhibitors represented by formulas: ##STR1##

    ______________________________________                                        Designation  Reagent or Fragment                                              ______________________________________                                        Ala          alanine                                                          Arg          arginine                                                         Asn          asparagine                                                       Asp          aspartic acid                                                    Cys          cysteine                                                         Gln          glutamine                                                        Glu          glutamic acid                                                    Gly          glycine                                                          His          histidine                                                        Ile          isoleucine                                                       Leu          leucine                                                          Lys          lysine                                                           Met          methionine                                                       Phe          phenylalanine                                                    Pro          proline                                                          Ser          serine                                                           Thr          threonine                                                        Trp          tryptophan                                                       Tyr          tyrosine                                                         Val          valine.                                                          ______________________________________                                    

Definitions

The following terms are employed herein:

The term "active site" refers to any or all of the following sites inICE: the substrate binding site, the site where an inhibitor binds andthe site where the cleavage of substrate occurs. The active site ischaracterized by at least amino acid residues: 173, 176, 177, 178, 179,180, 236, 237, 238, 239, 244, 248, 283, 284, 285, 290, 338, 339, 340,341, 342, 343, 344, 345, 348, 352, 381, 383, using the sequence andnumbering according to Thornberry et al., supra.

The terms "P binding pocket", "S subsite", "S pocket", and the like,refer to binding subsites, or portions of the substrate binding site onthe ICE molecule. The amino acid residues of the substrate are givendesignations according to their position relative to the scissile bond,i.e. the bond which is broken by the protease. The residues aredesignated P1, P2, etc., for those extending toward the N-terminus ofthe substrate and P1', P2', etc., for those extending toward theC-terminus of the substrate. The portions of an inhibitor whichcorrespond to the P or P' residues of the substrate are also labeled P1,P1', etc., by analogy with the substrate. The binding subsites of theICE molecule which receive the residues labeled P1, P1', etc., aredesignated S1, S1', etc., or may alternately be designated "the P1binding pocket", "the P1' binding pocket", etc. [I. Schechter and A.Berger, "On the Size of the Active Site in Proteases", Biochem. Biophys.Res. Commun., vol. 27, pp. 157-162 (1967).]

The terms "P2 binding pocket" or "S2 subsite" of the ICE active site areequivalent and are defined as the space surrounded by amino acidresidues Pro-290, Val-338 or Trp-340.

The terms "P3 binding pocket" or "S3 subsite" of the ICE active site areequivalent and are defined as the space surrounded by amino acidresidues Pro-177, Arg-178, Thr-180, Arg-341 or Pro-343.

The terms "P4 binding pocket" or "S4 subsite" of the ICE active site areequivalent and are defined as the space surrounded by amino acidresidues His-342, Met-345, Val-348, Arg-352, Asp-381, Arg-383 orTrp-340.

The terms "P1 binding pocket" or "S1 subsite" of the ICE active site areequivalent and are defined as the space surrounded by amino acidresidues Arg-179, His-237, Gln-283, or Arg-341.

The terms "P' binding pocket" or "S' subsite" of the ICE active site areequivalent and are defined as the space surrounded by amino acidresidues Phe-173, Ile-176, His-237, Gly-238, Ile-239, Cys-244 orHis-248.

The term "hydrophobic" refers to a moiety which tends not to dissolve inwater and is fat-soluble. Hydrophobic moieties include, but are notlimited to, hydrocarbons, such as alkanes, alkenes, alkynes,cycloalkanes, cycloalkenes, cycloalkynes and aromatic compounds, such asaryls, certain saturated and unsaturated heterocycles and moieties thatare substantially similar to the side chains of hydrophobic natural andunnatural α-amino acids, including valine, leucine, isoleucine,methionine, phenylanine, α-amino isobutyric acid, alloisoleucine,tyrosine, and tryptophan.

The term "moderately hydrophobic" refers to a hydrophobic moiety inwhich one or two carbon atoms have been replaced with more polar atoms,such as oxygen or nitrogen.

The term "heterocycle" or "heterocyclic" refers to a stable mono- orpolycyclic compound which may optionally contain one or two double bondsor may optionally contain one or more aromatic rings. Each heterocycleconsists of carbon atoms and from one to four heteroatoms independentlyselected from a group including nitrogen, oxygen, and sulfur. As usedherein, the terms "nitrogen heteroatoms" and "sulphur heteroatoms"include any oxidized form of nitrogen or sulfur and the quaternized formof any basic nitrogen. Heterocycles defined above include, for example,pyrimidinyl, tetrahydroquinolyl, tetrahydroisoquinonlinyl, purinyl,pyrimidyl, indolinyl, benzimidazolyl, imidazolyl, imidazolinoyl,imidazolidinyl, quinolyl, isoquinolyl, indolyl, pyridyl, pyrrolyl,pyrrolinyl, pyrazolyl, pyrazinyl, quinoxolyl, piperidinyl, morpholinyl,thiamorpholinyl, furyl, thienyl, triazolyl, thiazolyl, β-carbolinyl,tetrazolyl, thiazolidinyl, benzofuranoyl, thiamorpholinyl sulfone,benzoxazolyl, oxopiperidinyl, oxopyrrolidinyl, oxoazepinyl, azepinyl,isoxazolyl, tetrahydropyranyl, tetrahydrofuranyl, thiadiazolyl,benzodioxolyl, benzothienyl, tetrahydrothiophenyl and sulfolanyl.Further heterocycles are described in A. R. Katritzky and C. W. Rees,eds., Comprehensive Heterocyclic Chemistry: The Structure, Reactions,Synthesis and Use of Heterocyclic Compounds, Vol. 1-8, Pergamon Press,NY (1984).

The term "cycloalkyl" refers to a mono- or polycyclic group whichcontains 3 to 15 carbons and may optionally contain one or two doublebonds. Examples include cyclohexyl, adamantyl and norbornyl.

The term "aryl" refers to a mono- or polycyclic group which contains 6,10, 12, or 14 carbons in which at least one ring is aromatic. Examplesinclude phenyl, naphthyl and biphenyl.

The term "heteroaromatic" refers to a mono- or polycyclic group whichcontains 1 to 15 carbon atoms and from 1 to 4 heteroatoms, each of whichis selected independently from a group including sulphur, nitrogen andoxygen, and which additionally contains from 1 to 3 five or six memberedrings, at least one of which is aromatic.

The term "alpha-amino acid" (α-amino acid) refers to both the naturallyoccurring amino acids and other "non-protein" α-amino acids commonlyutilized by those in the peptide chemistry arts when preparing syntheticanalogues of naturally occurring peptides, including D and L forms. Thenaturally occurring amino acids are glycine, alanine, valine, leucine,isoleucine, serine, methionine, threonine, phenylalanine, tyrosine,tryptophan, cysteine, proline, histidine, aspartic acid, asparagine,glutamic acid, glutamine, γ-carboxyglutamic acid, arginine, ornithineand lysine. Examples of "non-protein" alpha-amino acids includehydroxylysine, homoserine, homotyrosine, homophenylalanine, citrulline,kynurenine, 4-aminophenylalanine, 3-(2-naphthyl)-alanine,3-(1-naphthyl)-alanine, methionine sulfone, t-butyl-alanine,t-butylglycine, 4-hydroxyphenylglycine, aminoalanine, phenylglycine,vinylalanine, propargyl-glycine, 1,2,4-triazolo-3-alanine,4,4,4-trifluoro-threonine, thyronine, 6-hydroxytryptophan,5-hydro-xytryptophan, 3-hydroxykynurenine, 3-aminotyrosine,trifuoromethylalanine, 2-thienylalanine, (2-(4-pyridyl)ethyl)-cysteine,3,4-dimethoxy-phenylalanine, 3-(2-thiazolyl)-alanine, ibotenic acid,1-amino-1-cyclopentane-carboxylic acid, 1-amino-1-cyclohexanecarboxylicacid, quisqualic acid, 3-trifuoromethylphenylalanine,4-trifuoro-methylphenylalanine, cyclohexylalanine, cyclo-hexylglycine,thiohistidine, 3-methoxytyrosine, elastatinal, norleucine, norvaline,alloisoleucine, homoarginine, thioproline, dehydroproline,hydroxyproline, isonipectotic acid, homoproline, cyclohexylglycine,α-amino-n-butyric acid, cyclohexylalanine, aminophenylbutyric acid,phenylalanines substituted at the ortho, meta, or para position of thephenyl moiety with one or two of the following: a (C₁ -C₄) alkyl, a (C₁-C₄) alkoxy, halogen or nitro groups or substituted with amethylenedioxy group; β-2- and 3-thienylalanine, β-2- and3-furanylalanine, β-2-, 3- and 4-pyridylalanine, β-(benzothienyl-2- and3-yl)alanine, β-(1- and 2-naphthyl)alanine, O-alkylated derivatives ofserine, threonine or tyrosine, S-alkylated cysteine, S-alkylatedhomocysteine, O-sulfate, O-phosphate and O-carboxylate esters oftyrosine, 3-sulfo-tyrosine, 3-carboxy-tyrosine, 3-phospho-tyrosine,4-methane sulfonic acid ester of tyrosine, 4-methane phosphonic acidester of tyrosine, 3,5-diiodotyrosine, 3-nitro-tyrosine, ε-alkyl lysine,and delta-alkyl ornithine. Any of these α-amino acids may be substitutedwith a methyl group at the alpha position, a halogen at any aromaticresidue on the α-amino side chain, or an appropriate protective group atthe O, N, or S atoms of the side chain residues. Appropriate protectivegroups are disclosed in "Protective Groups In Organic Synthesis," T. W.Greene and P. G. M. Wuts, J. Wiley & Sons, NY, N.Y., 1991.

The term "α-amino acid side chain residue" refers to a chemical moietywhich is attached to the α-carbon of an alpha-amino acid.

The term "bioisosteric replacement for --CO₂ H" refers to group whichmay substitute for a carboxylic acid group in bioactive molecules.Examples of such groups are disclosed in Christopher A. Lipinski,"Bioisosteres in Drug Design" Annual Reports In Medical Chemistry, 21,pp. 286-88 (1986), and in C. W. Thornber, "Isosterism and MolecularModification in Drug Design" Chemical Society Reviews, pp. 563-580(1979).

The term "association" is used in reference to a condition of proximitybetween an inhibitor or portions thereof to an ICE molecule or portionsthereof wherein the juxtaposition is energetically favored byelectrostatic or van der Waals interactions.

The term "hydrogen bond" refers to a favorable interaction that occurswhenever a suitable donor atom, X, bearing a proton, H, and a suitableacceptor atom, Y, have a separation of between 2.5 Å and 3.5 Å and wherethe angle X--H - - - Y is greater than 90 degrees. Suitable donor andacceptor atoms are well understood in medicinal chemistry (G. C.Pimentel and A. L. McClellan, The Hydrogen Bond, Freeman, San Francisco,1960; R. Taylor and O. Kennard, "Hydrogen Bond Geometry in OrganicCrystals", Accounts of Chemical Research, 17, pp. 320-326 (1984)).

The term "salt bridge" refers to the non-covalent attractive interactionbetween a positively charged moiety (P) and a negatively charged moiety(N) when the distance between the centers of mass of P and N is between2 and 6 Angstroms. In calculating the center of mass, atoms which maycontain a formal charge and atoms immediately adjacent to these areincluded. For example, a salt bridge may be formed between thepositively charged guanidinium side chain of an arginine residue and thenegative charged carboxylate side chain of a glutamate residue. Saltbridges are well understood in medicinal chemistry (L. Stryer,Biochemistry, Freeman, San Francisco, (1975); K. A. Dill, "DominantForces in Protein Folding", Biochemistry, 29, No. 31, pp. 7133-7155,(1990)).

The term "center of mass" refers to a point in three-dimensional spacewhich represents a weighted average position of the masses that make upan object.

The terms "backbone chain" and "backbone" refer to the portion of apolypeptide which comprises the repeating unit --CO--CH--NH--.

The term "scaffold" refers to a structural building block which formsthe basis of an ICE inhibitor according to this invention. Variousmoieties and functional groups are intended to be appended to thescaffold. The scaffolds of this invention are thus depicted having openvalences. Various scaffolds of ICE inhibitors according to thisinvention include the portions: ##STR2## In those scaffolds, the NH andCO or SO₂ moieties represent a first and a second hydrogen bondingmoiety, said moieties each being capable of forming a hydrogen bond witha backbone atom of ICE, said backbone atom being selected from the groupconsisting of the carbonyl oxygen of Arg-341, the amide --NH-- ofArg-341, the carbonyl oxygen of Ser-339 and the amide --NH-- of Ser-339.

The term "substitute" refers to the replacement of a hydrogen atom in acompound with a substituent group. In the present invention, thosehydrogen atoms which form a part of a hydrogen bonding moiety which iscapable of forming a hydrogen bond with the carbonyl oxygen of Arg-341of ICE or the carbonyl oxygen of Ser-339 of ICE are excluded fromsubstitution. These excluded hydrogen atoms include those which comprisean --NH-- group which is alpha to a Z or a --CO-- group and are depictedas --NH-- rather than an X group or some other designation in thefollowing diagrams: (a) through (t), (v) through (y), and (I) through(VIID).

The term "straight chain" refers to a contiguous unbranching string ofcovalently bound members, i.e. atoms, which form a portion of a ring.The straight chain and the ring of which it forms a part may besubstituted, but these substituents are not a part of the straightchain.

The term "K_(i) " refers to a numerical measure of the effectiveness ofa compound in inhibiting the activity of a target enzyme such as ICE.Lower values of K_(i) reflect higher effectiveness. The K_(i) value is aderived by fitting experimentally determined rate data to standardenzyme kinetic equations (see I. H. Segel, Enzyme Kinetics,Wiley-Interscience, 1975).

The term "minimize" refers to the systematic altering of the atomicgeometry of a molecule or molecular complex so that any further minorperturbation of the atomic geometry would cause the total energy of thesystem as measured by a molecular mechanics force-field to increase.Minimization and molecular mechanics force-fields are well understood incomputational chemistry [U. Burkert and N. L. Allinger, MolecularMechanics, ACS Monograph 177, American Chemical Society, Washington,D.C. 1982 pages 59-78].

The term "strain energy" is used in this application to refer to thedifference between the free conformation energy of a compound and thebound conformation energy of that compound when bound to ICE. The strainenergy can be determined by the following steps: Evaluate the energy ofthe molecule when it has the conformation necessary for binding to ICE.Then minimize and reevaluate the energy--this is the free conformationenergy. The strain energy for binding of a potential inhibitor to ICE isthe difference between the free conformation energy and the boundconformation energy. In a preferred embodiment, the strain energy of aninhibitor of the present invention is less than about 10 kcal/mol.

The term "patient" as used in this application refers to any mammal,especially humans.

The term "pharmaceutically effective amount" refers to an amounteffective in treating or ameliorating an IL-1 mediated disease in apatient. The term "prophylactically effective amount" refers to anamount effective in preventing or substantially lessening IL-1 mediateddisease in a patient.

The term "pharmaceutically acceptable carrier or adjuvant" refers to anon-toxic carrier or adjuvant that may be administered to a patient,together with a compound of this invention, and which does not destroythe pharmacological activity thereof.

The term "pharmaceutically acceptable derivative" means anypharmaceutically acceptable salt, ester, or salt of such ester, of acompound of this invention or any other compound which, uponadministration to a recipient, is capable of providing (directly orindirectly) a compound of this invention or an anti-ICE activemetabolite or residue thereof.

Pharmaceutically acceptable salts of the compounds of this inventioninclude, for example, those derived from pharmaceutically acceptableinorganic and organic acids and bases. Examples of suitable acidsinclude hydrochloric, hydrobromic, sulfuric, nitric, perchloric,fumaric, maleic, phosphoric, glycolic, lactic, salicylic, succinic,toluene-p-sulfonic, tartaric, acetic, citric, methanesulfonic, formic,benzoic, malonic, naphthalene-2-sulfonic and benzenesulfonic acids.Other acids, such as oxalic, while not in themselves pharmaceuticallyacceptable, may be employed in the preparation of salts useful asintermediates in obtaining the compounds of the invention and theirpharmaceutically acceptable acid addition salts. Salts derived fromappropriate bases include alkali metal (e.g., sodium), alkaline earthmetal (e.g., magnesium), ammonium and N--(C₁₋₄ alkyl)₄ ⁺ salts.

This invention also envisions the "quaternization" of any basicnitrogen-containing groups of the compounds disclosed herein. The basicnitrogen can be quaternized with any agents known to those of ordinaryskill in the art including, for example, lower alkyl halides, such asmethyl, ethyl, propyl and butyl chloride, bromides and iodides; dialkylsulfates including dimethyl, diethyl, dibutyl and diamyl sulfates; longchain halides such as decyl, lauryl, myristyl and stearyl chlorides,bromides and iodides; and aralkyl halides including benzyl and phenethylbromides. Water or oil-soluble or dispersible products may be obtainedby such quaternization.

The ICE inhibitors of this invention may contain one or more"asymmetric" carbon atoms and thus may occur as racemates and racemicmixtures, single enantiomers, diastereomeric mixtures and individualdiastereomers. All such isomeric forms of these compounds are expresslyincluded in the present invention. Each stereogenic carbon may be of theR or S configuration. Although specific compounds and scaffoldsexemplified in this application may be depicted in a particularstereochemical configuration, compounds and scaffolds having either theopposite stereochemistry at any given chiral center or mixtures thereofare also envisioned.

The ICE inhibitors of this invention may comprise ring structures whichmay optionally be substituted at carbon, nitrogen or other atoms byvarious substituents. Such ring structures may be singly or multiplysubstituted. Preferably, the ring structures contain between 0 and 3substituents. When multiply substituted, each substituent may be pickedindependently of any other substituent as long as the combination ofsubstituents results in the formation of a stable compound.

Combinations of substituents and variables envisioned by this inventionare only those that result in the formation of stable compounds. Theterm "stable", as used herein, refers to compounds which possessstability sufficient to allow manufacture and administration to a mammalby methods known in the art. Typically, such compounds are stable at atemperature of 40° C. or less, in the absence of moisture or otherchemically reactive conditions, for at least a week.

DETAILED DESCRIPTION OF THE INVENTION

In order that the invention herein described may be more fullyunderstood, the following detailed description is set forth.

We have discovered that compounds possessing the following novelcombination of features are surprisingly effective ICE inhibitors:

a) a first and a second hydrogen bonding moiety, each of said moietiesbeing capable of forming a hydrogen bond with a different backbone atomof ICE, said backbone atom being selected from the group consisting ofthe carbonyl oxygen of Arg-341, the amide --NH-- group of Arg-341, thecarbonyl oxygen of Ser-339 and the amide --NH-- group of Ser-339;

b) a first and a second moderately hydrophobic moiety, said moietieseach being capable of associating with a separate binding pocket of ICEwhen the inhibitor is bound thereto, said binding pocket being selectedfrom the group consisting of the P2 binding pocket, the P3 bindingpocket, the P4 binding pocket and the P' binding pocket; and

c) an electronegative moiety comprising one or more electronegativeatoms, said atoms being attached to the same atom or to adjacent atomsin the moiety and said moiety being capable of forming one or morehydrogen bonds or salt bridges with residues in the P1 binding pocket ofICE.

Preferably, any moderately hydrophobic moiety associating with the P2binding pocket of ICE does so in such a way that:

a) the distance from the center of mass of the moderately hydrophobicmoiety in the P2 binding pocket to the carbonyl oxygen of Arg-341 of ICEis between about 7.1 Å and about 12.5 Å;

b) the distance from the center of mass of the moderately hydrophobicmoiety in the P2 binding pocket to the amide nitrogen of Arg-341 of ICEis between about 6.0 Å and about 12 Å; and

c) the distance from the center of mass of the moderately hydrophobicmoiety in the P2 binding pocket to the carbonyl oxygen of Ser-339 of ICEis between about 3.7 Å and about 9.5 Å.

Preferably, any moderately hydrophobic moiety associating with the P3binding pocket of ICE does so in such a way that:

a) the distance from the center of mass of the moderately hydrophobicmoiety in the P3 binding pocket to the carbonyl oxygen of Arg-341 of ICEis between about 3.9 Å and about 9.5 Å;

b) the distance from the center of mass of the moderately hydrophobicmoiety in the P3 binding pocket to the amide nitrogen of Arg-341 of ICEis between about 5.4 Å and about 11 Å; and

c) the distance from the center of mass of the moderately hydrophobicmoiety in the P3 binding pocket to the carbonyl oxygen of Ser-339 of ICEis between about 7.0 Å and about 13 Å.

Preferably, any moderately hydrophobic moiety associating with the P4binding pocket of ICE does so in such a way that:

a) the distance from the center of mass of the moderately hydrophobicmoiety in the P4 binding pocket to the carbonyl oxygen of Arg-341 of ICEis between about 4.5 Å and about 7.5 Å;

b) the distance from the center of mass of the moderately hydrophobicmoiety in the P4 binding pocket to the amide nitrogen of Arg-341 of ICEis between about 5.5 Å and about 8.5 Å; and

c) the distance from the center of mass of the moderately hydrophobicmoiety in the P4 binding pocket to the carbonyl oxygen of Ser-339 of ICEis between about 8 Å and about 11 Å.

Preferably, any moderately hydrophobic moiety associating with the P'binding pocket of ICE does so in such a way that:

a) the distance from the center of mass of the moderately hydrophobicmoiety in the P' binding pocket to the carbonyl oxygen of Arg-341 of ICEis between about 11 Å and about 16 Å;

b) the distance from the center of mass of the moderately hydrophobicmoiety in the P' binding pocket to the amide nitrogen of Arg-341 of ICEis between about 10 Å and about 15 Å; and

c) the distance from the center of mass of the moderately hydrophobicmoiety in the P' binding pocket to the carbonyl oxygen of Ser-339 of ICEis between about 8 Å and about 12 Å.

More preferably, all of the above associative conditions are met in thecompounds of this invention.

The practitioner skilled in the art will appreciate that there are anumber of means to design the inhibitors of the present invention. Thesesame means may be used to select a candidate compound for screening asan ICE inhibitor. This design or selection may begin with selection ofthe various moieties which fill binding pockets.

There are a number of ways to select moieties to fill individual bindingpockets. These include visual inspection of a physical model or computermodel of the active site and manual docking of models of selectedmoieties into various binding pockets. Modeling software that is wellknown and available in the art may be used. These include QUANTA[Molecular Simulations, Inc., Burlington, Mass., 1992], SYBYL [MolecularModeling Software, Tripos Associates, Inc., St. Louis, Mo., 1992], AMBER[S. J. Weiner, P. A. Kollman, D. A. Case, U. C. Singh, C. Ghio, G.Alagona, and P. Weiner, J. Am. Chem. Soc., vol. 106, pp. 765-784(1984)], or CHARMM [B. R. Brooks, R. E. Bruccoleri, B. D. Olafson, D. J.States, S Swaminathan, and M. Karplus, J. Comp. Chem. vol. 4, pp.187-217 (1983)]. This modelling step may be followed by energyminimization with standard molecular mechanics forcefields such asCHARMM and AMBER. In addition, there are a number of more specializedcomputer programs to assist in the process of selecting the bindingmoieties of this invention. These include:

1. GRID (Goodford, P. J. A Computational Procedure for DeterminingEnergetically Favorable Binding Sites on Biologically ImportantMacromolecules. J. Med. Chem., 28, pp. 849-857 (1985)). GRID isavailable from Oxford University, Oxford, UK.

2. MCSS (Miranker, A.; Karplus, M.

Functionality Maps of Binding Sites: A Multiple Copy Simultaneous SearchMethod. Proteins: Structure. Function and Genetics, 11, pp. 29-34(1991)). MCSS is available from Molecular Simulations, Burlington, Mass.

3. AUTODOCK (Goodsell, D. S.; Olsen, A. J. Automated Docking ofSubstrates to Proteins by Simmulated Annealing. PROTEINS: Structure.Function and Genetics, 8, pp. 195-202 (1990)). AUTODOCK is availablefrom the Scripps Research Institute, La Jolla, Calif.

4. DOCK (Kuntz, I. D.; Blaney, J. M.; Oatley, S. J.; Langridge, R.;Ferrin, T. E. A Geometric Approach to Macromolecule-Ligand Interactions.J. Mol. Biol., 161, pp. 269-288 (1982)). DOCK is available from theUniversity of California, San Francisco, Calif.

Once suitable binding moieties have been selected, they can be assembledinto a single inhibitor. This assembly may be accomplished by connectingthe various moieties to a central scaffold. The assembly process may,for example, be done by visual inspection followed by manual modelbuilding, again using software such as Quanta or Sybyl. A number ofother programs may also be used to help select ways to connect thevarious moieties. These include:

1. CAVEAT (Bartlett, P. A.; Shea, G. T.; Telfer, S. J.; Waterman, S.CAVEAT: A Program to Facilitate the Structure-Derived Design ofBiologically Active Molecules. In "Molecular Recognition in Chemical andBiological Problems," Special Pub., Royal Chem. Soc., 78, pp. 182-196(1989)). CAVEAT is available from the University of California,Berkeley, Calif.

2. 3D Database systems such as MACCS-3D (MDL Information Systems, SanLeandro, Calif.). This area has been recently reviewed by Martin(Martin, Y. C. 3D Database Searching in Drug Design. J. Med. Chem., 35,pp. 2145-2154 (1992)).

3. HOOK (available from Molecular Simulations, Burlington, Mass.).

In addition to the above computer assisted modeling of inhibitorcompounds, the inhibitors of this invention may be constructed "de novo"using either an empty active site or optionally including some portionsof a known inhibitor. Such methods are well known in the art. Theyinclude, for example:

1. LUDI (Bohm, H. J. The Computer Program LUDI: A New Method for the DeNovo Design of Enzyme Inhibitors. J. Comp. Aid. Molec. Design., 6, 61-78(1992)). LUDI is available from Biosym Technologies, San Diego, Calif.

2. LEGEND (Nishibata, Y., Itai, A., Tetrahedron, 47, 8985 (1991)).LEGEND is available from Molecular Simultations, Burlington, Mass..

3. LeapFrog (available from Tripos associates, St. Louis, Mo.).

A number of techniques commonly used for modeling drugs may be employed(For a review, see: Cohen, N. C.; Blaney, J. M.; Humblet, C.; Gund, P.;Barry, D. C., "Molecular Modeling Software and Methods for MedicinalChemistry", J. Med. Chem., 33, pp. 883-894 (1990)). There are likewise anumber of examples in the chemical literature of techniques that can beapplied to specific drug design projects. For a review, see: Navia, M.A. and Murcko, M. A., "The Use of Structural Information in DrugDesign", Current Opinions in Structural Biology, 2, pp. 202-210 (1992).Some examples of these specific applications include: Baldwin, J. J. etal., "Thienothiopyran-2-sulfonamides: Novel Topically Active CarbonicAnhydrase Inhibitors for the Treatment of Glaucoma", J. Med. Chem., 32,pp. 2510-2513 (1989); Appelt, K. et al., "Design of Enzyme InhibitorsUsing Iterative Protein Crystallographic Analysis", J. Med. Chem., 34,pp. 1925-1934 (1991); and Ealick, S. E. et al., "Application ofCrystallographic and Modeling Methods in the Design of Purine NucleotidePhosphorylase Inhibitors" Proc. Nat. Acad. Sci. USA, 88, pp. 11540-11544(1991).

Using the novel combination of steps of the present invention, theskilled artisan can advantageously avoid time consuming and expensiveexperimentation to determine enzymatic inhibition activity of particularcompounds. The method also is useful to facilitate rational design ofICE inhibitors and therapeutic and prophylactic agents againstIL-1-mediated diseases. Accordingly, the present invention relates tosuch inhibitors.

A variety of conventional techniques may be used to carry out each ofthe above evaluations as well as the evaluations necessary in screeninga candidate compound for ICE inhibiting activity. Generally, thesetechniques involve determining the location and binding proximity of agiven moiety, the occupied space of a bound inhibitor, the deformationenergy of binding of a given compound and electrostatic interactionenergies. Examples of conventional techniques useful in the aboveevaluations include: quantum mechanics, molecular mechanics, moleculardynamics, Monte Carlo sampling, systematic searches and distancegeometry methods (G. R. Marshall, Ann. Rev. Pharmacol. Toxicol., 27, p.193 (1987)). Specific computer software has been developed for use incarrying out these methods. Examples of programs designed for such usesinclude: Gaussian 92, revision E.2 (M. J. Frisch, Gaussian, Inc.,Pittsburgh, Pa. ©1993); AMBER, version 4.0 (P. A. Kollman, University ofCalifornia at San Francisco, ©1993); QUANTA/CHARMM [MolecularSimulations, Inc., Burlington, Mass. 1992]; and Insight II/Discover(Biosysm Technologies Inc., San Diego, Calif. 1992). These programs maybe implemented, for instance, using a Silicon Graphics Indigo 2workstation or IBM RISC/6000 workstation model 550. Other hardwaresystems and software packages will be known and of evident applicabilityto those skilled in the art.

Different classes of active ICE inhibitors, according to this invention,may interact in similar ways with the various binding pockets of the ICEactive site. The spatial arrangement of these important groups is oftenreferred to as a pharmacophore. The concept of the pharmacophore hasbeen well described in the literature (D. Mayer, C. B. Naylor, I. Motoc,and G. R. Marshall, J. Comp. Aided Molec. Design vol. 1, pp. 3-16(1987); A. Hopfinger and B. J. Burke, in Concepts and Applications ofMolecular Similarity, M. A. Johnson and G. M. Maggiora, ed., Wiley(1990)).

Different classes of ICE inhibitors of this invention may also usedifferent scaffolds or core structures, but all of these cores willallow the necessary moieties to be placed in the active site such thatthe specific interactions necessary for binding may be obtained. Thesecompounds are best defined in terms of their ability to match thepharmacophore, i.e., their structural identity relative to the shape andproperties of the active site of ICE.

The ICE inhibitors of one embodiment of this invention comprise a firstand a second hydrogen bonding moiety, a first and a second moderatelyhydrophobic moiety, and an electronegative moiety which comprise or arecovalently bound to one of the following scaffolds: ##STR3##

The ICE inhibitors of another embodiment (A) of this invention are thoseof formula α: ##STR4## wherein:

X₁ is CH or N;

g is 0 or 1;

each J is independently selected from the group consisting of --H, --OH,and --F, provided that when a first and second J are bound to a C andsaid first J is --OH, said second J is --H;

m is 0, 1, or 2;

T is --Ar₃, --OH, --CF₃, --CO--CO₂ H, --CO₂ H or any bioisostericreplacement for --CO₂ H;

R₁ is selected from the group consisting of the following formulae, inwhich any ring may optionally be singly or multiply substituted at anycarbon by Q₁, at any nitrogen by R₅, or at any atom by ═O, --OH, --CO₂H, or halogen, and in which any saturated ring may optionally beunsaturated at one or two bonds: ##STR5##

R₂₀ is selected from the group consisting of: ##STR6## wherein each ringC is independently chosen from the group consisting of benzo, pyrido,thieno, pyrrolo, furano, thiazolo, isothiazolo, oxazolo, isoxazolo,pyrimido, imidazolo, cyclopentyl, and cyclohexyl;

R₃ is

--CN,

--CH═CH--R₉,

--CH═N--O--R₉,

--(CH₂)₁₋₃ --T₁ --R₉,

--CJ₂ --R₉,

--CO--R₁₃, or ##STR7##

each R₄ is independently selected from the group consisting of:

--H,

--Ar₁,

--R₉,

--T₁ --R₉, and

--(CH₂)₁,2,3 --T₁ --R₉,

each T₁ is independently selected from the group consisting of:

--CH═CH--,

--O--,

--S--,

--SO--,

--SO₂ --,

--NR₁₀ --,

--NR₁₀ --CO--,

--CO--,

--O--CO--,

--CO--O--,

--CO--NR₁₀ --,

--O--CO--NR₁₀ --,

--NR₁₀ --CO--O--,

--NR₁₀ --CO--NR₁₀ --,

--SO₂ --NR₁₀ --,

--NR₁₀ --SO₂ --, and

--NR₁₀ --SO₂ --NR₁₀ --,

each R₅ is independently selected from the group consisting of:

--H,

--Ar₁,

--CO--Ar₁,

--SO₂ --Ar₁,

--R₉,

--CO--R₉,

--CO--O--R₉,

--SO₂ --R₉, ##STR8##

R₆ and R₇ taken together form a saturated 4-8 member carbocyclic ring orheterocyclic ring containing --O--, --S--, or --NH--, or

R₇ is --H and R₆ is

--H

--Ar₁,

--R₉, or

--(CH₂)₁,2,3 --T₁ --R₉ ;

each R₉ is a C₁₋₆ straight or branched alkyl group optionally singly ormultiply substituted by --OH, --F, or ═O and optionally substituted withone or two Ar₁ groups;

each R₁₀ is independently selected from the group consisting of --H or aC₁₋₆ straight or branched alkyl group;

each R₁₃ is independently selected from the group consisting of --Ar₂and --R₄ ;

each Ar₁ is a cyclic group independently selected from the setconsisting of an aryl group which contains 6, 10, 12, or 14 carbon atomsand between 1 and 3 rings, a cycloalkyl group which contains between 3and 15 carbon atoms and between 1 and 3 rings, said cycloalkyl groupbeing optionally benzofused, and a heterocycle group containing between5 and 15 ring atoms and between 1 and 3 rings, said heterocycle groupcontaining at least one heteroatom group selected from --O--, --S--,--SO--, --SO₂ --, ═N--, and --NH--, said heterocycle group optionallycontaining one or more double bonds, said heterocycle group optionallycomprising one or more aromatic rings, and said cyclic group optionallybeing singly or multiply substituted by ═O, --OH, perfluoro C₁₋₃ alkyl,or --Q₁ ;

each Ar₂ is independently selected from the following group, in whichany ring may optionally be substituted by --Q₁ : ##STR9##

Ar₃ is a cyclic group selected from the set consisting of a phenyl ring,a 5-membered heteroaromatic ring, and a 6-membered heteroaromatic ring,said heteroaromatic rings comprising 1-3 heteroatom groups selected from--O--, --S--, --SO--, --SO₂ --, ═N--, and --NH--, said cyclic groupoptionally being singly or multiply substituted with ═O, --OH, halogen,perfluoro C₁₋₃ alkyl, or --CO₂ H;

each Q₁ is independently selected from the group consisting of:

--Ar₁

--R₉,

--T₁ --R₉, and

--(CH₂)₁,2,3 --T₁ --R₉,

provided that when --Ar₁ is substituted with a Q₁ group which comprisesone or more additional --Ar₁ groups, said additional --Ar₁ groups arenot substituted with Q₁ ;

each X is independently selected from the group consisting of ═N--, and═CH--;

each X₂ is independently selected from the group consisting of --O--,--CH₂ --, --NH--, --S--, --SO--, and --SO₂ ; each X₃ is independentlyselected from the group consisting of --CH₂ --, --S--, --SO--, and --SO₂--;

each X₄ is independently selected from the group consisting of --CH₂ --and --NH--;

each X₅ is independently selected from the group consisting of ##STR10##

X₆ is CH or N, provided that when X₆ is N in the R₁ group labeled (o)and X₅ is CH and X₂ is CH₂ the ring of the R₁ group labeled (o) must besubstituted by Q₁ or benzofused;

each Y is independently selected from the group consisting of --O-- and--S--;

each Z is independently CO or SO₂,

each a is independently 0 or 1,

each c is independently 1 or 2,

each d is independently 0, 1, or 2, and

each e is independently 0, 1, 2, or 3.

The ICE inhibitors of another embodiment (B) of this invention are thoseof formula α: ##STR11## wherein:

X₁ is --CH;

g is 0 or 1;

each J is independently selected from the group consisting of --H, --OH,and --F, provided that when a first and second J are bound to a C andsaid first J is --OH, said second J is --H;

m is 0, 1, or 2;

T is --OH, --CO--CO₂ H, --CO₂ H or any bioisosteric replacement for--CO₂ H;

R₁ is selected from the group consisting of the following formulae, inwhich any ring may optionally be singly or multiply substituted at anycarbon by Q₁, at any nitrogen by R₅, or at any atom by ═O, --OH, --CO₂H, or halogen, any saturated ring may optionally be unsaturated at oneor two bonds; and wherein R₁ (e) and R₁ (y) are optionally benzofused;##STR12##

R₂₀ is selected from the group consisting of: ##STR13##

wherein each ring C is independently chosen from the group consisting ofbenzo, pyrido, thieno, pyrrolo, furano, thiazolo, isothiazolo, oxazolo,isoxazolo, pyrimido, imidazolo, cyclopentyl, and cyclohexyl;

R₃ is

--CN,

--CH═CH--R₉,

--CH═N--O--R₉,

--(CH₂)₁₋₃ --T₁ --R₉,

--CJ₂ --R₉,

--CO--R₁₃, or ##STR14##

each R₄ is independently selected from the group consisting of:

--H,

--Ar₁,

--R₉,

--T₁ --R₉, and

--(CH₂)₁,2,3 --T₁ --R₉,

each T, is independently selected from the group consisting of:

--CH═CH--,

--O--,

--S--,

--SO--,

--SO₂ --,

--NR₁₀ --,

--NR₁₀ --CO --,

--CO--,

--O--CO--,

--CO--O--,

--CO--NR₁₀ --,

--O--CO--NR₁₀ --,

--NR₁₀ --CO--O--,

--NR₁₀ --CO--NR₁₀ --,

--SO₂ --NR₁₀ --,

--NR₁₀ --SO₂ --, and

--NR₁₀ --SO₂ --NR₁₀ --,

each R₅ is independently selected from the group consisting of:

--H,

--Ar₁,

--CO--Ar₁,

--SO₂ --Ar₁,

--CO--NH₂,

--SO₂ --NH₂,

--R₉,

--CO--R₉,

--CO--O--R₉,

--SO₂ --R₉, ##STR15##

R₆ and R₇ taken together form a saturated 4-8 member carbocyclic ring orheterocyclic ring containing --O--, --S--, or --NH--; or

R₇ is --H and R₆ is:

--H,

--Ar₁,

--R₉,

--(CH₂)₁,2,3 --T₁ --R₉, or

an α-amino acid side chain residue;

each R₉ is a C₁₋₆ straight or branched alkyl group optionally singly ormultiply substituted by --OH, --F, or ═O and optionally substituted withone or two Ar₁ groups;

each R₁₀ is independently selected from the group consisting of --H or aC₁₋₆ straight or branched alkyl group;

each R₁₃ is independently selected from the group consisting of --Ar₂,--R₄ and ##STR16##

each Ar₁ is a cyclic group independently selected from the setconsisting of an aryl group which contains 6, 10, 12, or 14 carbon atomsand between 1 and 3 rings, a cycloalkyl group which contains between 3and 15 carbon atoms and between 1 and 3 rings, said cycloalkyl groupbeing optionally benzofused, and a heterocycle group containing between5 and 15 ring atoms and between 1 and 3 rings, said heterocycle groupcontaining at least one heteroatom group selected from --O--, --S--,--SO--, --SO₂ --, ═N--, and --NH--, said heterocycle group optionallycontaining one or more double bonds, said heterocycle group optionallycomprising one or more aromatic rings, and said cyclic group optionallybeing singly or multiply substituted by --NH₂, --CO₂ H, --Cl, --F, --Br,--I, --NO₂, --CN, ═O, --OH, -perfluoro C₁₋₃ alkyl, ##STR17##

each Ar₂ is independently selected from the following group, in whichany ring may optionally be singly or multiply substituted by --Q₁ and--Q₂ : ##STR18##

each Q₁ is independently selected from the group consisting of

--Ar

--O--Ar₁

--R₉,

--T₁ --R₉, and

--(CH₂)₁,2,3 --T₁ --R₉ ;

each Q₂ is independently selected from the group consisting of --OH,--NH₂, --CO₂ H, --Cl, --F, --Br, --I, --NO₂, --CN, --CF₃, and ##STR19##

provided that when --Ar₁ is substituted with a Q₁ group which comprisesone or more additional --Ar₁ groups, said additional --Ar₁ groups arenot substituted with Q₁ ;

each X is independently selected from the group consisting of ═N--, and═CH--;

each X₂ is independently selected from the group consisting of --O--,--CH₂ --, --NH--, --S--, --SO--, and --SO₂ --;

each X₃ is independently selected from the group consisting of --CH₂ --,--S--, --SO--, and --SO₂ --;

each X₄ is independently selected from the group consisting of --CH₂ --and --NH--;

each X₅ is independently selected from the group consisting of ##STR20##

X₆ is CH or N, provided that when X₆ is N in the R₁ group labeled (o)and X₅ is CH and X₂ is CH₂ the ring of the R₁ group labeled (o) must besubstituted by Q₁ or benzofused;

each Y is independently selected from the group consisting of --O-- and--S--, and --NH;

each Z is independently CO or SO₂,

each a is independently 0 or 1,

each c is independently 1 or 2,

each d is independently 0, 1, or 2, and

each e is independently 0, 1, 2, or 3,

provided that when

R₁ is (f),

R₆ is an α-amino acid side chain residue, and

R₇ is --H,

then (aa1) and (aa2) must be substituted with Q₁ ;

also provided that when

R₁ is (o),

g is 0,

J is --H,

m is 1,

R₆ is an α-amino acid side chain residue,

R₇ is --H,

X₂ is --CH₂ --,

X₅ is ##STR21## X₆ is ##STR22## and R₃ is ##STR23## or --CO--R₁₃, whenR₁₃ is:

--CH₂ --O--CO--Ar₁,

--CH₂ --S--CO--Ar₁,

--CH₂ --O--Ar₁,

--CH₂ --S--Ar₁, or

--R₄ when --R₄ is --H;

then the ring of the R₁ (o) group must be substituted with Q₁ orbenzofused; and

provided that when

R₁ is (w),

g is 0,

J is --H,

m is 1,

T is --CO₂ H or --CO--NH--OH,

X₂ is O,

R₅ is benzyloxycarbonyl, and

ring C is benzo,

then R₃ cannot be --CO--R₁₃ when:

R₁₃ is --CH₂ --O--Ar₁ and

Ar₁ is 1-phenyl-3-chloro- or 3-trifluoromethyl-pyrazole-5-yl;

or when

R₁₃ is --CH₂ --O--CO--Ar₁ and

Ar₁ is 2,6-dichlorophenyl.

Preferred forms of the R₁ group (a) for embodiments A and B are:##STR24##

Preferred forms of the R₁ group (b) are: ##STR25##

Preferred forms of the R₁ group (c) are: ##STR26##

provided that when R₁ is (c1),

g is 0,

J is --H,

m is 1,

T is --CO₂ H,

X is N,

R₅ is benzyloxycarbonyl, and

R₆ is --H,

then R₃ cannot be --CO--R₁₃ when

R₁₃ is --CH₂ --O--Ar₁ and

Ar₁ is a chloro-substituted 1-phenyl-3-trifluoromethyl-pyrazole-5-yl, orwhen

R₁₃ is --CH₂ --O--CO--Ar₁ and

Ar₁ is 2,6-dichlorophenyl,

and when the 2-position of the scaffold ring is substituted withpara-fluoro-phenyl;

Preferred forms of the R₁ group (d) are: ##STR27##

Preferred forms of the R₁ group (e) are: ##STR28##

which is optionally benzofused; ##STR29##

provided that when R₁ is (e4)

g is 0,

J is --H,

m is 1,

T is --CO₂ H,

R₅ is benzyloxycarbonyl, and

C is 1,

then R₃ cannot be --CO--R₁₃ when

R₁₃ is --CH₂ --O--Ar₁ and

Ar₁ is 1-phenyl-3-trifluoromethyl-pyrazole-5-yl, wherein the phenyl isoptionally substituted with a chlorine atom; or when

R₁₃ is --CH₂ --O--CO--Ar₁ and

Ar₁ is 2,6-dichlorophenyl,

and when the 2-position of the scaffold ring is substituted withpara-fluoro-phenyl; and

also provided that when

R₁ is (e7),

g is 0,

J is --H,

m is 1,

T is --CO₂ H or --CO--NH--OH,

R₅ is a protective group for the N atom of an amino acid side chainresidue, and

each c is 1,

then R₃ cannot be --CO--R₁₃ when R₁₃ is:

--CH₂ --O--CO--Ar₁,

--CH₂ --S--CO--Ar₁,

--CH₂ --O--Ar₁, or

--CH₂ --S--Ar₁,

Preferred forms of the R₁ group (g) are: ##STR30##

Preferred forms of the R₁ group (h) are: ##STR31##

Preferred forms of the R₁ group (i) are: ##STR32##

Preferred forms of the R₁ group (j) are: ##STR33##

Preferred forms of the R₁ group (k) are: ##STR34##

Preferred forms of the R₁ group (1) are: ##STR35##

Preferred forms of the R₁ group (m) are: ##STR36##

Preferred forms of the R₁ group (n) are: ##STR37##

Preferred forms of the R₁ group (o) are: ##STR38##

A preferred form of the R₁ group (o) of embodiment B is: ##STR39##wherein X₂ is --O--, --S--, --SO₂ --, or --NH--.

For embodiments A and B, preferred forms of the R₁ group (p) are:##STR40##

Preferred forms of the R₁ group (q) are: ##STR41##

Preferred forms of the R₁ group (r) are: ##STR42##

Preferred forms of the R₁ group (s) are: ##STR43##

Preferred forms of the R₁ group (t) are: ##STR44##

Preferred forms of the R₁ group (v) are: ##STR45##

A preferred form of the R1 group (w) of embodiment B is: ##STR46##wherein X₂ is --O--, --S--, --SO₂ -- or --NH--.

The preferred compounds of embodiments A and B of this invention arethose which employ formula α, wherein:

X₁ is CH;

g is O;

J is --H;

m is 0 or 1 and T is --Ar₃, --CO--CO₂ H, --CO₂ H or any bioisostericreplacement for --CO₂ H, or

m is 1 or 2 and T is --OH, --CF₃, or --CO₂ H;

more preferably m is 1 and T is --CO₂ H; ##STR47##

R₂₀ is ##STR48## wherein ring C is benzo;

R₃ is

--CO--R₁₃, or ##STR49##

most preferably R₃ is any one of 1), 2) or 3) as follows: 1) --CO--Ar₂,2) --CO--R₉ where R₉ is C₃₋₆ alkyl substituted with two Ar₁ groups orone Ar₁ group itself substituted with an Ar₁ group, --C₁₋₂ --Ar₁, --Cl,--CH₃, or --CF₃, or 3) --(CH₂)₁,2 --T₁ --R₉ where T₁ is --O-- or --S--and R₉ is C₁₋₂ alkyl substituted with two Ar₁ groups or one Ar₁ groupitself substituted with an Ar₁ group, C₁₋₂ --Ar₁, --Cl, --CH₃, or --CF₃;

R₄ is --H or --R₉ ;

T₁ is

--O--,

--S--,

--CO--,

--O--CO--, or

--SO₂ --;

when R₁ is (a), (b), (k), or (m), R₅ is preferably --Ar₁ or C₁₋₄ --Ar₁ ;

when R₁ is (c) , (e) , (f), (o) , or (r) , R₅ is preferably --SO₂ --Ar₁,--SO₂ --R₉, or --CO--C₁₋₄ --Ar₁ ;

R₇ is --H and R₆ is C₁₋₄ --Ar₁ ;

R₁₀ is --H or a C₁₋₃ straight or branched alkyl group;

R₁₃ is --Ar₂ ;

Ar₁ is phenyl, naphthyl, pyridyl, benzothiazolyl, thienyl, benzothienyl,benzoxazolyl, 2-indanyl, or indolyl;

Ar₂ is preferably substituted with --Ar₁, or --C₁₋₄ --Ar₁ ;

Ar₃ is phenyl, thiophene, thiazole, pyridine, or oxazole; and

Q₁ is --R₉ or --(CH₂)₁,2 --T₁ --(CH₂)₁₋₃ --Ar₁ where T₁ is --O-- or--S--.

In connection with this continuation-in-part, we now prefer thecompounds of embodiment B of this invention which employ formula α,wherein:

X₁ is --CH;

g is O;

J is --H;

m is 0 or 1 and T is --CO--CO₂ H, or any bioisosteric replacement for--CO₂ H; or

m is 1 and T is --CO₂ H;

R₁ is selected from the group consisting of the following formulae, inwhich any ring may optionally be singly or multiply substituted at anycarbon by Q₁, at any nitrogen by R₅, or at any atom by ═O, --OH, --CO₂H, or halogen, and wherein (e) is optionally benzofused: ##STR50##

R₂₀ is ##STR51##

and c is 1;

ring C is benzo optionally substituted with --C₁₋₃ alkyl, --O--C₁₋₃alkyl, --Cl, --F or --CF₃ ;

R₃ is:

--CO--R₁₃, or ##STR52##

more preferably R₃ is any one of 1), 2) or 3) as follows: 1) --CO--Ar₂ ;2) --CO--R₉ where R₉ is C₁₋₅ alkyl substituted with an Ar₁ ; or 3) --CH₂--T₁ --R₉ where T₁ is --O-- or --S-- and R₉ is C₁₋₂ alkyl substitutedwith one Ar₁ group;

R₄ is --H or --R₉ ;

T₁ is:

--O--,

--S--,

--CO--,

--O--CO--, or

--SO₂ --;

when R₁ is (a) or (b), R₅ is preferably --H, and

when R₁ is (c), (e) , (f), (o), (r), (w), (x) or (y), R₅ is preferably:

--CO--Ar₁

--SO₂ --Ar₁,

--CO--NH₂,

--CO--NH--Ar₁

--CO--R₉,

--CO--O--R₉,

--SO₂ --R₉, or

--CO--NH--R₉,

R₇ is --H and R₆ is

--H,

--R₉ or

--Ar₁ ;

R₉ is C₁₋₆ straight or branched alkyl group optionally substituted with═O and optionally substituted with --Ar₁ ;

R₁₀ is --H or a C₁₋₃ straight or branched alkyl group;

R₁₃ is:

--H,

--R₉,

--Ar₂, or

--CH₂ --T₁ --R₉,

more preferably where --Ar₂ is (hh) and where (hh) is optionallysubstituted singly or multiply with --C₁₋₆ alkyl, --O--C₁₋₆ alkyl,--NH--C₁₋₆ alkyl, --N--(C₁₋₆ alkyl)₂, --S--C₁₋₆ alkyl, --Cl, --F, --CF₃,or ##STR53##

Ar₁ is phenyl, naphthyl, pyridyl, benzothiazolyl, thienyl, benzothienyl,benzoxazolyl, 2-indanyl, or indolyl substituted with --O--C₁₋₃ alkyl,--NH--C₁₋₃ alkyl, --N--(C₁₋₃ alkyl)₂, --Cl, --F, --CF₃, --C₁₋₃ alkyl, or##STR54##

preferably where Ar₂ is: ##STR55##

each X is independently selected from the group consisting of ═N--, and═CH--;

each X₂ is independently selected from the group consisting of --O--,--CH₂ --, --NH--, --S--, --SO--, and --SO₂ --;

each X₅ is independently selected from the group consisting of ##STR56##

X₆ is ##STR57## and

Z is C═O;

provided that when

R₁ is (f),

R₆ is an α-amino acid side chain residue, and

R₇ is --H,

then (aa1) and (aa2) must be substituted with Q₁ ;

also provided that when

R₁ is (o),

g is 0,

J is --H,

m is 1,

R₆ is an α-amino acid side chain residue,

R₇ is --H,

X₂ is --CH₂ --,

X₅ is ##STR58## X₆ is ##STR59## and R₃ is ##STR60## or --CO--R₁₃, when

R₁₃ is:

--CH₂ --O--CO--Ar₁,

--CH₂ --S--CO--Ar₁,

--CH₂ --O--Ar₁,

--CH₂ --S--Ar₁, or

--R₄ when --R₄ is --H;

then the ring of the R₁ (o) group must be substituted with Q₁ orbenzofused; and

provided that when

R₁ is (w),

g is 0,

J is --H,

m is 1,

T is --CO₂ H,

X₂ is O,

R₅ is benzyloxycarbonyl, and

ring C is benzo,

then R₃ cannot be --CO--R₁₃ when:

R₁₃ is --CH₂ --O--Ar₁ and

Ar₁ is 1-phenyl-3-trifluoromethyl-pyrazole-5-yl, wherein the phenyl isoptionally substituted with a chlorine atom;

or when R₁₃ is --CH₂ -O--CO--Ar₁, wherein Ar₁ is 2,6-dichlorophenyl.

A preferred form of R₁₃ is --CH₂ --O--R₉, wherein R₉ is a C₁₋₆ straightor branched alkyl group optionally substituted with ═O and optionallysubstituted with Ar₁ ;

another preferred form of R₁₃ is CH₂ --S--R₉, wherein R₉ is a C₁₋₆straight or branched alkyl group optionally substituted with Ar₁ ;

another preferred form of R₁₃ is CH₂ --O--R₉ wherein R₉ is a C₁₋₆straight or branched alkyl group optionally substituted with Ar₁ ;

another preferred form of R₁₃ is H.

A more preferred form of the R₁ group (a) is: ##STR61##

optionally substituted with Q₁, wherein

R₅ is --H;

R₇ is --H; and

Z is C═O;

a more preferred form of the R₁ group (b) is: ##STR62##

optionally substituted with Q₁, wherein

R₅ is --H;

R₇ is --H; and

Z is C═O;

more preferred forms of the R₁ group (c) are: ##STR63##

provided that when R₁ is (c1),

g is 0,

J is --H,

m is 1,

T is --CO₂ H,

X is N,

R₅ is benzyloxycarbonyl, and

R₆ is --H,

then R₃ cannot be --CO--R₁₃ when

R₁₃ is --CH₂ --O--Ar₁ and

Ar₁ is 1-phenyl-3-trifluoromethyl-pyrazole-5-yl wherein the phenyl isoptionally substituted with a chlorine atom; or when

R₁₃ is --CH₂ --O--CO--Ar₁, wherein

Ar₁ is 2,6-dichlorophenyl,

and wherein the 2-position of the scaffold ring is substituted withpara-fluoro-phenyl;

more preferred forms of the R₁ group (e) are: ##STR64## wherein C is 2;and ##STR65## which is optionally benzofused, wherein c is 1 or 2;

provided that when R₁ is (e4),

g is 0,

J is --H,

m is 1,

T is --CO₂ H,

R₅ is benzyloxycarbonyl, and

c is 1,

then R₃ cannot be --CO--R₁₃ when

R₁₃ is --CH₂ --O--Ar₁ and

Ar₁ is 1-phenyl-3-trifluoromethyl-pyrazole-5-yl wherein the phenyl isoptionally substituted with a chlorine atom; or when

R₁₃ is --CH₂ --O--CO--Ar₁, wherein

Ar₁ is 2,6-dichlorophenyl,

and wherein the 2-position of the scaffold ring is substituted withpara-fluoro-phenyl; and

also provided that when

R₁ is (e7),

g is 0,

J is --H,

m is 1,

T is --CO₂ H, --CO--NH--OH, or a bioisosteric replacement for --CO₂ H,

R₅ is a protective group for the N atom of an α-amino acid side chainresidue, and

each c is 1,

then R₃ cannot be --CO--R₁₃ when

R₁₃ is:

--CH₂ --O--CO--Ar₁,

--CH₂ --S--CO--Ar₁,

--CH₂ --O--Ar₁, or

--CH₂ --S--Ar₁.

a more preferred form of the R₁ group (f) is ##STR66##

a more preferred form of the R₁ group (g) is: ##STR67##

R₂₀ is (aa1) optionally substituted singly or multiply with Q₁ ; and

Z is C═O;

a more preferred form of the R₁ group (h) is: ##STR68##

R₂₀ is (aa1) optionally substituted singly or multiply with Q₁ ; and

Z is C═O;

more preferred forms of the R₁ group (o) are: ##STR69## wherein d is 1or 2; and ##STR70##

more preferred forms of the R₁ group (r) are: ##STR71## optionallysubstituted with Q₁ ;

a more preferred form of the R₁ group (w) is: ##STR72##

X₂ is:

--NH--,

--S--,

--O--, or

--SO₂ --;

optionally substituted with R₅ or Q₁ at X₂ when X₂ is --N--; and

ring C is benzo substituted with --C₁₋₃ alkyl, --O--C₁₋₃ alkyl, --Cl,--F or --CF₃.

When R₁ is: ##STR73## preferred compounds of this invention include butare not limited to: ##STR74##

A preferred compound of embodiment B of this invention employs formulaα, wherein the R₁ is: ##STR75##

Preferred compounds of this embodiment include but are not limited to:##STR76##

When R₁ is: ##STR77## preferred compounds of this invention include butare not limited to: ##STR78##

A preferred compound of embodiment B of this invention employs formulaα, wherein:

R₁ is: ##STR79##

and c is 2;

m is 1;

T is --CO₂ H; and

R₃ is --CO--R₁₃.

Preferred compounds of this embodiment include but are not limited to:##STR80##

When R₁ is: ##STR81## preferred compounds of this invention include butare not limited to: ##STR82##

When R₁ is: ##STR83## preferred compounds of this invention include butare not limited to: ##STR84##

When R₁ is: ##STR85## preferred compounds of this invention include butare not limited to: ##STR86##

A preferred compound of embodiment B of this invention employs formulaα, wherein:

R₁ is: ##STR87##

X₂ is --NH--;

m is 1;

T is --CO₂ H;

R₃ is --CO--R₁₃.

Preferred compounds of this embodiment include but are not limited to:##STR88##

When R₁ is: ##STR89##

optionally substituted with Q₁ ;

preferred compounds of embodiment B of this invention include but arenot limited to: ##STR90##

When R₁ is: ##STR91## preferred compounds of this invention include butare not limited to: ##STR92##

The ICE inhibitors of another embodiment (C) of this invention arerepresented by the formula α: ##STR93##

wherein the ring is optionally substituted with one or more R groups,preferably 0, 1 or 2; and wherein:

R₁ is R₅ --(A)_(p) --;

R₅ is selected from the group consisting of:

--H,

--Ar₁,

--CO--Ar₁,

--SO₂ --Ar₁,

--R₉,

--CO--R₉,

--CO--O--R₉,

--SO₂ --R₉, ##STR94##

each A is independently selected from the group consisting of anyα-amino acid;

p is 0, 1, 2, 3 or 4;

Y is:

--O--,

--S-- or

--NH;

R is:

--H,

--O--C₁₋₆ alkyl,

--NH(C₁₋₆ alkyl),

--N(C₁₋₆ alkyl)₂,

--S--C₁₋₆ alkyl,

--C₁₋₆ alkyl, or

Q₂ ;

each R₉ is a C₁₋₆ straight or branched alkyl group optionally singly ormultiply substituted by --OH, --F, or ═O and optionally substituted withone or two Ar₁ groups;

each R₁₀ is independently selected from the group consisting of --H or aC₁₋₆ straight or branched alkyl group;

each T₁ is independently selected from the group consisting of:

--CH═CH--,

--O--,

--S--,

--SO--,

--SO₂ --,

--NR₁₀ --,

--NR₁₀ --CO--,

--CO--,

--O--CO--,

--CO--O--,

--CO--NR₁₀ --,

--O--CO--NR₁₀ --,

--NR₁₀ --CO--O--,

--NR₁₀ --CO--NR₁₀ --,

--SO₂ --NR₁₀ --,

--NR₁₀ --SO₂ --, and

--NR₁₀ --SO₂ --NR₁₀ --,

each Ar₁ is a cyclic group independently selected from the setconsisting of an aryl group which contains 6, 10, 12, or 14 carbon atomsand between 1 and 3 rings, a cycloalkyl group which contains between 3and 15 carbon atoms and between 1 and 3 rings, said cycloalkyl groupbeing optionally benzofused, and a heterocycle group containing between5 and 15 ring atoms and between 1 and 3 rings, said heterocycle groupcontaining at least one heteroatom group selected from --O--, --S--,--SO--, --SO₂ --, ═N--, and --NH--, said heterocycle group optionallycontaining one or more double bonds, said heterocycle group optionallycomprising one or more aromatic rings, and said cyclic group optionallybeing singly or multiply substituted by: --NH₂, --CO₂ H, --Cl, --F,--Br, --I, --NO₂, --CN, ═O, --OH, -perfluoro C₁₋₃ alkyl, ##STR95## or--Q₁ ;

each Q₁ is independently selected from the group consisting of:

--Ar₁

--R₉,

--T₁ --R₉, and

--(CH₂)₁,2,3 --T₁ --R₉ ;

each Q₂ is independently selected from the group consisting of --OH,--NH₂, --CO₂ H, --Cl, --F, --Br, --I, --NO₂, --CN, --CF₃, and ##STR96##

provided that when --Ar₁ is substituted with a Q₁ group which comprisesone or more additional --Ar₁ groups, said additional --Ar₁ groups arenot substituted with Q₁.

Preferred compounds of embodiment C of this invention include but arenot limited to: ##STR97##

Preferred compounds of embodiment C of this invention are also those inwhich each A is independently selected from the group consisting of theα-amino acids:

alanine,

histidine,

lysine,

phenylalanine,

proline,

tyrosine,

valine,

leucine,

isoleucine,

glutamine,

methionine,

homoproline,

3-(2-thienyl) alanine, and

3-(3-thienyl) alanine.

The ICE inhibitors of another embodiment (D) of this invention arerepresented by the formula π: ##STR98## wherein:

R₁ is R₅ -(A)_(p) -;

each T₁ is independently selected from the group consisting of:

--CH═CH--,

--O--,

--S--,

--SO₂ --,

--NR₁₀ --,

--NR₁₀ --CO--,

--CO--,

--O--CO--,

--CO--O--,

--CO--NR₁₀ --,

--O--CO--NR₁₀ --,

--NR₁₀ --CO--O--,

--NR₁₀ --CO--NR₁₀ --,

--SO₂ --NR₁₀ --,

--NR₁₀ --SO₂ --, and

--NR₁₀ --SO₂ --NR₁₀ --;

R₅ is selected from the group consisting of:

--H,

--Ar₁,

--CO--Ar₁,

--SO₂ --Ar₁,

--R₉,

--CO--R₉,

--CO--O--R₉,

--SO₂ --R₉, ##STR99##

each A is independently selected from the group consisting of anyα-amino acid;

p is 0, 1, 2, 3 or 4;

each R₉ is a C₁₋₆ straight or branched alkyl group optionally singly ormultiply substituted by --OH, --F, or ═O and optionally substituted withan Ar₁ group;

each R₁₀ is independently selected from the group consisting of --H or aC₁₋₆ straight or branched alkyl group;

Ar₁ is a cyclic group independently selected from the set consisting ofan aryl group which contains 6, 10, 12, or 14 carbon atoms and between 1and 3 rings, a cycloalkyl group which contains between 3 and 15 carbonatoms and between 1 and 3 rings, said cycloalkyl group being optionallybenzofused, and a heterocycle group containing between 5 and 15 ringatoms and between 1 and 3 rings, said heterocycle group containing atleast one heteroatom group selected from --O--, --S--, --SO--, --SO₂ --,═N--, and --NH--, said heterocycle group optionally containing one ormore double bonds, said heterocycle group optionally comprising one ormore aromatic rings, and said cyclic group optionally being singly ormultiply substituted by --NH₂, --CO₂ H, --Cl, --F, --Br, --I, --NO₂,--CH, ═O, --OH, -perfluoro C₁₋₃ alkyl, or ##STR100##

Preferred compounds of embodiment D of this invention are those in whichR₉ is a C₁₋₄ straight or branched alkyl substituted with Ar₁ when Ar₁ isphenyl.

Preferred compounds of embodiment D of this invention include but arenot limited to: ##STR101##

Preferred compounds of embodiment D of this invention are also those inwhich A is independently selected from the group consisting of theα-amino acids:

alanine,

histidine,

lysine,

phenylalanine,

proline,

tyrosine,

valine,

leucine,

isoleucine,

glutamine,

methionine,

homoproline,

3-(2-thienyl) alanine, and

3-(3-thienyl) alanine.

The ICE inhibitors of another embodiment (E) of this invention arerepresented by formula v: ##STR102## wherein:

m is 0, 1, or 2;

T is --CO₂ H, or any bioisosteric replacement for --CO₂ H,

R₃ is

--CN,

--COR₁₃, or ##STR103##

R₅ is selected from the group consisting of:

--H,

--Ar₁,

--CO--Ar₁,

--SO₂ --Ar₁,

--R₉,

--CO--R₉,

--CO--O--R₉,

--SO₂ --R₉, ##STR104##

each A is independently selected from the group consisting of anyα-amino acid;

p is 2 or 3;

each R₉ is a C₁₋₆ straight or branched alkyl group optionally singly ormultiply substituted by --OH, --F, or ═O and optionally substituted withone Ar₁ group;

each T₁ is independently selected from the group consisting of:

--CH═CH--,

--O--,

--S--,

--SO--,

--SO₂ --,

--NR₁₀ --,

--NR₁₀ --CO--,

--CO--,

--O--CO--,

--CO--O--,

--CO--NR₁₀ --,

--O--CO--NR₁₀ --,

--NR₁₀ --CO--O--,

--NR₁₀ --CO--NR₁₀ --,

--SO₂ --NR₁₀ --,

--NR₁₀ --SO₂ --, and

--NR₁₀ --SO₂ --NR₁₀ --;

each R₁₀ is independently selected from the group consisting of --H or a--C₁₋₆ straight or branched alkyl group;

each R₁₃ is independently selected from the group consisting of H, R₉,Ar₂, and CH₂ T₁ R₉ ;

each Ar₁ is a cyclic group independently selected from the setconsisting of an aryl group which contains 6, 10, 12, or 14 carbon atomsand between 1 and 3 rings, a cycloalkyl group which contains between 3and 15 carbon atoms and between 1 and 3 rings, said cycloalkyl groupbeing optionally benzofused, and a heterocycle group containing between5 and 15 ring atoms and between 1 and 3 rings, said heterocycle groupcontaining at least one heteroatom group selected from --O--, --S--,--SO--, --SO₂ --, ═N--, and --NH--, said heterocycle group optionallycontaining one or more double bonds, said heterocycle group optionallycomprising one or more aromatic rings, and said cyclic group optionallybeing singly or multiply substituted by --NH₂, --CO₂ H, --Cl, --F, --Br,--I, --NO₂, --CN, ═O, --OH, -perfluoro C₁₋₃ alkyl, ##STR105## or --Q₁ ;and

each Ar₂ is independently selected from the following group, in whichany ring may optionally be singly or multiply substituted by --Q₁ and--Q₂ : ##STR106##

each Q₁ is independently selected from the group consisting of:

--Ar₁

--O--Ar₁

--R₉,

--T₁ --R₉, and

--(CH₂)₁,2,3 --T₁ --R₉ ;

each Q₂ is independently selected from the group consisting of --OH,--NH₂, --CO₂ H, --Cl, --F, --Br, --I, --NO₂, --CN, --CF₃, and ##STR107##

provided that when --Ar₁ is substituted with a Q₁ group which comprisesone or more additional --Ar₁ groups, said additional --Ar₁ groups arenot substituted with Q₁.

Preferred compounds of embodiment E of this invention include but arenot limited to: ##STR108##

Preferred compounds of embodiment E of this invention are also those inwhich A is independently selected from the group consisting the α-aminoacids:

alanine,

histidine,

lysine,

phenylalanine,

proline,

tyrosine,

valine,

leucine,

isoleucine,

glutamine,

methionine,

homoproline,

3-(2-thienyl) alanine, and

3-(3-thienyl) alanine.

The ICE inhibitors of another embodiment (F) of this invention arerepresented by formula δ: ##STR109## wherein:

R₁ is R₅ --(A)_(p) --;

R₅ is selected from the group consisting of:

--H,

--Ar₁,

--CO--Ar₁,

--SO₂ --Ar₁,

--R₉,

--CO--R₉,

--CO--O--R₉,

--SO₂ --R₉, ##STR110##

each A is independently selected from the group consisting of anyα-amino acid;

p is 0, 1, 2, 3 or 4;

each R₉ is a C₁₋₆ straight or branched alkyl group optionally singly ormultiply substituted by --OH, --F, or ═O and optionally substituted withone Ar₁ group;

each R₁₀ is independently selected from the group consisting of --H or aC₁₋₆ straight or branched alkyl group;

each T₁ is independently selected from the group consisting of:

--CH═CH--,

--O--,

--S--,

--SO--,

each Ar₁ is a cyclic group independently selected from the setconsisting of an aryl group which contains 6, 10, 12, or 14 carbon atomsand between 1 and 3 rings, a cycloalkyl group which contains between 3and 15 carbon atoms and between 1 and 3 rings, said cycloalkyl groupbeing optionally benzofused, and a heterocycle group containing between5 and 15 ring atoms and between 1 and 3 rings, said heterocycle groupcontaining at least one heteroatom group selected from --O--, --S--,--SO--, --SO₂ --, ═N--, and --NH--, said heterocycle group optionallycontaining one or more double bonds, said heterocycle group optionallycomprising one or more aromatic rings, and said cyclic group optionallybeing singly or multiply substituted by --NH₂, --CO₂ H, --Cl, --F, --Br,--I, --NO₂, --CN, ═O, --OH, -perfluoro C₁₋₃ alkyl, ##STR111## or --Q₁ ;and

each Ar₂ is independently selected from the following group, in whichany ring may optionally be singly or multiply substituted by --Q₁ and--Q₂ : ##STR112##

each Q₁ is independently selected from the group consisting of:

--Ar₁

--O--Ar₁

--R₉,

--T₁ --R₉, and

--(CH₂)₁,2,3 --T₁ --R₉ ;

each Q₂ is independently selected from the group consisting of --OH,--NH₂, --CO₂ H, --Cl, --F, --Br, --I, --NO₂, --CN, --CF₃, and ##STR113##

provided that when --Ar₁ is substituted with a Q₁, group which comprisesone or more additional --Ar₁ groups, said additional --Ar₁ groups arenot substituted with Q₁ ;

each X is independently selected from the group consisting of ═N--, and═CH--; and

each Y is independently selected from the group consisting of --O--,--S--, and --NH.

Preferred compounds of embodiment F of this invention include but arenot limited to: ##STR114##

Preferred compounds of embodiment F of this indication are also those inwhich A is independently selected from the group consisting the α-aminoacids:

alanine,

histidine,

lysine,

phenylalanine,

proline,

tyrosine,

valine,

leucine,

isoleucine,

glutamine,

methionine,

homoproline,

3-(2-thienyl) alanine, and

3-(3-thienyl) alanine.

The compounds of this invention having a molecular weight of less thanor equal to about 700 Daltons, and more preferably between about 400 and600 Daltons, are preferred. These preferred compounds may be readilyabsorbed by the bloodstream of patients upon oral administration. Thisoral availability makes such compounds excellent agents fororally-administered treatment and prevention regimens against IL-1mediated diseases.

The ICE inhibitors of this invention may be synthesized usingconventional techniques. Advantageously, these compounds areconveniently synthesized from readily available starting materials.

The compounds of this invention are among the most readily synthesizedICE inhibitors known. Previously described ICE inhibitors often containfour or more chiral centers and numerous peptide linkages. The relativeease with which the compounds of this invention can be synthesizedrepresents an enormous advantage in the large scale production of thesecompounds.

It should be understood that the compounds of this invention may existin various equilibrium forms, depending on conditions including choiceof solvent, pH, and others known to the practitioner skilled in the art.All such forms of these compounds are expressly included in the presentinvention. In particular, many of the compounds of this invention,especially those which contain aldehyde or ketone groups in R₃ andcarboxylic acid groups in T, may take hemi-ketal (or hemi-acetal) orhydrated forms, as depicted below: ##STR115##

Depending on the choice of solvent and other conditions known to thepractitioner skilled in the art, compounds of this invention may alsotake acyloxy ketal, acyloxy acetal, ketal or acetal form: ##STR116##

In addition, it should be understood that the equilibrium forms of thecompounds of this invention may include tautomeric forms. All such formsof these compounds are expressly included in the present invention.

It should be understood that the compounds of this invention may bemodified by appropriate functionalities to enhance selective biologicalproperties. Such modifications are known in the art and include thosewhich increase biological penetration into a given biological system(e.g., blood, lymphatic system, central nervous system), increase oralavailability, increase solubility to allow administration by injection,alter metabolism and alter rate of excretion. In addition, the compoundsmay be altered to pro-drug form such that the desired compound iscreated in the body of the patient as the result of the action ofmetabolic or other biochemical processes on the pro-drug. Some examplesof pro-drug forms include ketal, acetal, oxime, and hydrazone forms ofcompounds which contain ketone or aldehyde groups, especially where theyoccur in the R₃ group of the compounds of this invention.

The compounds of this invention are excellent ligands for ICE.Accordingly, these compounds are capable of targeting and inhibitingevents in IL-1 mediated diseases, such as the conversion of precursorIL-1β to mature IL-1β and, thus, the ultimate activity of that proteinin inflammatory diseases, autoimmune diseases and neurodegenerativediseases. For example, the compounds of this invention inhibit theconversion of precursor IL-1β to mature IL-1β by inhibiting ICE. BecauseICE is-essential for the production of mature IL-1, inhibition of thatenzyme effectively blocks initiation of IL-1 mediated physiologicaleffects and symptoms, such as inflammation, by inhibiting the productionof mature IL-1. Thus, by inhibiting IL-1β precursor activity, thecompounds of this invention effectively function as IL-1 inhibitors.

The compounds of this invention may be employed in a conventional mannerfor the treatment of diseases which are mediated by IL-1. Such methodsof treatment, their dosage levels and requirements may be selected bythose of ordinary skill in the art from available methods andtechniques. For example, a compound of this invention may be combinedwith a pharmaceutically acceptable adjuvant for administration to apatient suffering from an IL-1 mediated disease in a pharmaceuticallyacceptable manner and in an amount effective to lessen the severity ofthat disease.

Alternatively, the compounds of this invention may be used incompositions and methods for treating or protecting individuals againstIL-1 mediated diseases over extended periods of time. The compounds maybe employed in such compositions either alone or together with othercompounds of this invention in a manner consistent with the conventionalutilization of ICE inhibitors in pharmaceutical compositions. Forexample, a compound of this invention may be combined withpharmaceutically acceptable adjuvants conventionally employed invaccines and administered in prophylactically effective amounts toprotect individuals over an extended period time against IL-1 mediateddiseases.

The compounds of this invention may also be co-administered with otherICE inhibitors to increase the effect of therapy or prophylaxis againstvarious IL-1-mediated diseases.

In addition, the compounds of this invention may be used in combinationeither conventional anti-inflammatory agents or with matrixmetalloprotease inhibitors, lipoxygenase inhibitors and antagonists ofcytokines other than IL-1β.

The compounds of this invention can also be administered in combinationwith immunomodulators (e.g., bropirimine, anti-human alpha interferonantibody, IL-2, GM-CSF, methionine enkephalin, interferon alpha,diethyldithiocarbamate, tumor necrosis factor, naltrexone and rEPO) orwith prostaglandins, to prevent or combat IL-1-mediated disease symptomssuch as inflammation.

When the compounds of this invention are administered in combinationtherapies with other agents, they may be administered sequentially orconcurrently to the patient. Alternatively, pharmaceutical orprophylactic compositions according to this invention may be comprisedof a combination of an ICE inhibitor of this invention and anothertherapeutic or prophylactic agent.

Pharmaceutical compositions of this invention comprise any of thecompounds of the present invention, and pharmaceutically acceptablesalts thereof, with any pharmaceutically acceptable carrier, adjuvant orvehicle. Pharmaceutically acceptable carriers, adjuvants and vehiclesthat may be used in the pharmaceutical compositions of this inventioninclude, but are not limited to, ion exchangers, alumina, aluminumstearate, lecithin, serum proteins, such as human serum albumin, buffersubstances such as phosphates, glycine, sorbic acid, potassium sorbate,partial glyceride mixtures of saturated vegetable fatty acids, water,salts or electrolytes, such as protamine sulfate, disodium hydrogenphosphate, potassium hydrogen phosphate, sodium chloride, zinc salts,colloidal silica, magnesium trisilicate, polyvinyl pyrrolidone,cellulose-based substances, polyethylene glycol, sodiumcarboxymethylcellulose, polyacrylates, waxes,polyethylene-polyoxypropylene-block polymers, polyethylene glycol andwool fat.

The pharmaceutical compositions of this invention may be administeredorally, parenterally, by inhalation spray, topically, rectally, nasally,buccally, vaginally or via an implanted reservoir. We prefer oraladministration. The pharmaceutical compositions of this invention maycontain any conventional non-toxic pharmaceutically-acceptable carriers,adjuvants or vehicles. The term parenteral as used herein includessubcutaneous, intracutaneous, intravenous, intramuscular,intra-articular, intrasynovial, intrasternal, intrathecal, intralesionaland intracranial injection or infusion techniques.

The pharmaceutical compositions may be in the form of a sterileinjectable preparation, for example, as a sterile injectable aqueous oroleaginous suspension. This suspension may be formulated according totechniques known in the art using suitable dispersing or wetting agents(such as, for example, Tween 80) and suspending agents. The sterileinjectable preparation may also be a sterile injectable solution orsuspension in a non-toxic parenterally-acceptable diluent or solvent,for example, as a solution in 1,3-butanediol. Among the acceptablevehicles and solvents that may be employed are mannitol, water, Ringer'ssolution and isotonic sodium chloride solution. In addition, sterile,fixed oils are conventionally employed as a solvent or suspendingmedium. For this purpose, any bland fixed oil may be employed includingsynthetic mono- or diglycerides. Fatty acids, such as oleic acid and itsglyceride derivatives are useful in the preparation of injectables, asare natural pharmaceutically-acceptable oils, such as olive oil orcastor oil, especially in their polyoxyethylated versions. These oilsolutions or suspensions may also contain a long-chain alcohol diluentor dispersant such as Ph. Helv or a similar alcohol.

The pharmaceutical compositions of this invention may be orallyadministered in any orally acceptable dosage form including, but notlimited to, capsules, tablets, and aqueous suspensions and solutions. Inthe case of tablets for oral use, carriers which are commonly usedinclude lactose and corn starch. Lubricating agents, such as magnesiumstearate, are also typically added. For oral administration in a capsuleform, useful diluents include lactose and dried corn starch. Whenaqueous suspensions are administered orally, the active ingredient iscombined with emulsifying and suspending agents. If desired, certainsweetening and/or flavoring and/or coloring agents may be added.

The pharmaceutical compositions of this invention may also beadministered in the form of suppositories for rectal administration.These compositions can be prepared by mixing a compound of thisinvention with a suitable non-irritating excipient which is solid atroom temperature but liquid at the rectal temperature and therefore willmelt in the rectum to release the active components. Such materialsinclude, but are not limited to, cocoa butter, beeswax and polyethyleneglycols.

Topical administration of the pharmaceutical compositions of thisinvention is especially useful when the desired treatment involves areasor organs readily accessible by topical application. For applicationtopically to the skin, the pharmaceutical composition should beformulated with a suitable ointment containing the active componentssuspended or dissolved in a carrier. Carriers for topical administrationof the compounds of this invention include, but are not limited to,mineral oil, liquid petroleum, white petroleum, propylene glycol,polyoxyethylene polyoxypropylene compound, emulsifying wax and water.Alternatively, the pharmaceutical composition can be formulated with asuitable lotion or cream containing the active compound suspended ordissolved in a carrier. Suitable carriers include, but are not limitedto, mineral oil, sorbitan monostearate, polysorbate 60, cetyl esterswax, cetearyl alcohol, 2-octyldodecanol, benzyl alcohol and water. Thepharmaceutical compositions of this invention may also be topicallyapplied to the lower intestinal tract by rectal suppository formulationor in a suitable enema formulation. Topically-transdermal patches arealso included in this invention.

The pharmaceutical compositions of this invention may be administered bynasal aerosol or inhalation. Such compositions are prepared according totechniques well-known in the art of pharmaceutical formulation and maybe prepared as solutions in saline, employing benzyl alcohol or othersuitable preservatives, absorption promoters to enhance bioavailability,fluorocarbons, and/or other solubilizing or dispersing agents known inthe art.

The IL-1 mediated diseases which may be treated or prevented by thecompounds of this invention include, but are not limited to,inflammatory diseases, autoimmune diseases and neurodegenerativediseases.

Inflammatory diseases which may be treated or prevented include, forexample, septic shock, septicemia, and adult respiratory distresssyndrome. Target autoimmune diseases include, for example, rheumatoid,arthritis, systemic lupus erythematosus, scleroderma, chronicthyroiditis, Graves' disease, autoimmune gastritis, insulin-dependentdiabetes mellitus, autoimmune hemolytic anemia, autoimmune neutropenia,thrombocytopenia, chronic active hepatitis, myasthenia gravis andmultiple sclerosis. And target neurodegenerative diseases include, forexample, amyotrophic lateral sclerosis, Alzheimer's disease, Parkinson'sdisease, and primary lateral sclerosis. The ICE inhibitors of thisinvention may also be used to promote wound healing. And the ICEinhibitors of this invention may be used to treat infectious diseases.

Although this invention focuses on the use of the compounds disclosedherein for preventing and treating IL-1-mediated diseases, the compoundsof this invention can also be used as inhibitory agents for othercysteine proteases.

The compounds of this invention are also useful as commercial reagentswhich effectively bind to ICE or other cysteine proteases. As commercialreagents, the compounds of this invention, and their derivatives, may beused to block proteolysis of a target peptide or may be derivatized tobind to a stable resin as a tethered substrate for affinitychromatography applications. These and other uses which characterizecommercial cysteine protease inhibitors will be evident to those ofordinary skill in the art.

In order that this invention be more fully understood, the followingexamples are set forth. These examples are for the purpose ofillustration only and are not to be construed as limiting the scope ofthe invention in any way.

EXAMPLE 1

The following example demonstrates a process of drug design whichembodies the present invention:

Step 1) Pick 2 hydrogen bonding moieties of ICE, here, the backbone C═Oand N--H of Arg-341.

Step 2) Pick a scaffold, here, a pyridone derivative, and confirm thatthe hydrogen bonding moieties of the scaffold are capable of formingsatisfactory hydrogen bonds with the hydrogen bonding moieties selectedin step 1. This confirmation is performed by using molecular mechanicstechniques to minimize the scaffold fragment in the context of theactive site of ICE. ##STR117##

Step 3) Pick a hydrophobic pocket, here, S2, as next target and ahydrophobic moiety, here, benzene. Minimize the benzene group within theS2 pocket to assure that substantial hydrophobic overlap is obtained.##STR118##

Step 4) Pick another hydrophobic pocket, here, S4, as the next targetand a hydrophobic moiety, here, benzene. Minimize the benzene groupwithin the S4 pocket to ensure that substantial hydrophobic overlap isobtained. ##STR119##

Step 5) Fill the S1 polar pocket with an electronegative moiety, here, acarboxylate sidechain provided by aspartic acid in which the C-terminushas been reduced to an aldehyde. Minimize to ensure that the carboxylatesidechain retains a favorable electrostatic interaction with the S1polar pocket. ##STR120##

Step 6) Link the scaffold with the moieties from steps 3, 4, and 5,preferably using the minimum number of bonds consistent with achemically reasonable structure. Minimize the entire composite moleculein the active site of ICE. ##STR121##

Step 7) Evaluate the energy of the molecule when it has the conformationnecessary for binding to ICE. Then minimize and reevaluate theenergy--this is the free conformation energy. The strain energy forbinding of the potential inhibitor to ICE is the difference between thefree conformation energy and the bound conformation energy. The strainenergy should be less than about 10 kcal/mol. In this case the boundconformation energy is -1.6 kcal/mol and the free conformation energy is-11.7 kcal/mol, for a strain energy of 10.1 kcal/mol.

Step 8) The inhibitor designed using the above steps has been made andhas been show to have a K_(i) of 150 nM.

EXAMPLE 2

We obtained inhibition constants (K_(i)) and IC₅₀ values for severalcompounds of this invention using the three methods described below:

1. Enzyme assay with UV-visible substrate

This assay is run using an Succinyl-Tyr-Val-Ala-Asp-pNitroanilidesubstrate. Synthesis of analogous substrates is described by L. A.Reiter (Int. J. Peptide Protein Res. 43, 87-96 (1994)). The assaymixture contains:

65 μl buffer (10 mM Tris, 1 mM DTT, 0.1% CHAPS @pH 8.1)

10 μl ICE (50 nM final concentration to give a rate of .sup.˜ 1 mOD/min)

5 μl DMSO/Inhibitor mixture

20 μl 400 μM Substrate (80 μm final concentration)

100 μl total reaction volume

The visible ICE assay is run in a 96-well microtiter plate. Buffer, ICEand DMSO (if inhibitor is present) are added to the wells in the orderlisted. The components are left to incubate at room temperature for 15minutes starting at the time that all components are present in allwells. The microtiter plate reader is set to incubate at 37° C. Afterthe 15 minute incubation, substrate is added directly to the wells andthe reaction is monitored by following the release of the chromophore(pNA) at 405-603 nm at 37° C. for 20 minutes. A linear fit of the datais performed and the rate is calculated in mOD/min. DMSO is only presentduring experiments involving inhibitors, buffer is used to make up thevolume to 100 μl in the other experiments.

2. Enzyme Assay with Fluorescent Substrate

This assay is run essentially according to Thornberry et al. (Nature356: 768-774 (1992)), using substrate 17 referenced in that article. Thesubstrate is: Acetyl-Tyr-Val-Ala-Asp-amino-4-methylcoumarin (AMC). Thefollowing components are mixed:

65 μl buffer(10 mM Tris,1 mM DTT, 0.1% CHAPS @pH 8.1)

10 μl ICE (2-10 μM final concentration)

5 μl DMSO/inhibitor solution

20 μl 150 μM Substrate (30 μM final)

100 μl total reaction volume

The assay is run in a 96 well microtiter plate. Buffer and ICE are addedto the wells. The components are left to incubate at 37° C. for 15minutes in a temperature-controlled wellplate. After the 15 minuteincubation, the reaction is started by adding substrate directly to thewells and the reaction is monitored @37° C. for 30 minutes by followingthe release of the AMC fluorophore using an excitation wavelength for380 nm and an emission wavelength of 460 nm. A linear fit of the datafor each well is performed and a rate is determined in fluorescenceunits per second.

For determination of enzyme inhibition constants (K_(i)) or the mode ofinhibition (competitive, uncompetitive or noncompetitive), the rate datadetermined in the enzyme assays at varying inhibitor concentrations arecomputer-fit to standard enzyme kinetic equations (see I. H. Segel,Enzyme Kinetics, Wiley-Interscience, 1975).

3. Cell assay

IL-1β Assay with a Mixed Population of Human Peripheral BloodMononuclear Cells (PBMC) or Enriched Adherent Mononuclear Cells

Processing of pre-IL-1β by ICE can be measured in cell culture using avariety of cell sources. Human PBMC obtained from healthy donorsprovides a mixed population of lymphocyte subtypes and mononuclear cellsthat produce a spectrum of interleukins and cytokines in response tomany classes of physiological stimulators. Adherent mononuclear cellsfrom PBMC provides an enriched source of normal monocytes for selectivestudies of cytokine production by activated cells.

Experimental Procedure

An initial dilution series of test compound in DMSO or ethanol isprepared, with a subsequent dilution into RPMI-10% FBS media (containing2 mM L-glutamine, 10 mM HEPES, 50 U and 50 ug/ml pen/strep) respectivelyto yield drugs at 4× the final test concentration containing 0.4% DMSOor 0.4% ethanol. The final concentration of DMSO is 0.1% for all drugdilutions. A concentration titration which brackets the apparent K_(i)for a test compound determined in an ICE inhibition assay is generallyused for the primary compound screen.

We generally test 5-6 compound dilutions and have performed the cellularcomponent of the assay in duplicate, with duplicate ELISA determinationson each cell culture supernatant.

PBMC Isolation and IL-1 Assay

Buffy coat cells isolated from one pint human blood (yielding 40-45 mlfinal volume plasma plus cells) are diluted with media to 80 ml andLeukoPREP separation tubes (Becton Dickinson) are each overlaid with 10ml of cell suspension. After 15 min centrifugation at 1500-1800×g, theplasma/media layer is aspirated and then the mononuclear cell layer iscollected with a Pasteur pipette and transferred to a 15 ml conicalcentrifuge tube (Corning). Media is added to bring the volume to 15 ml,gently mix the cells by inversion and centrifuge at 300×g for 15 min.Resuspend the PBMC pellet in a small volume of media, count cells andadjust to 6×10⁶ cells/ml.

For the cellular assay, add 1.0 ml of the cell suspension to each wellof a 24-well flat bottom tissue culture plate (Corning), 0.5 ml testcompound dilution and 0.5 ml LPS solution (Sigma #L-3012; 20 ng/mlsolution prepared in complete RPMI media; final LPS concentration 5ng/ml). The 0.5 ml additions of test compound and LPS are usuallysufficient to mix the contents of the wells. Three control mixtures arerun per experiment, with either LPS alone, solvent vehicle control,and/or additional media to adjust the final culture volume to 2.0 ml.The cell cultures are incubated for 16-18 hr at 37° C. in the presenceof 5% CO₂.

At the end of the incubation period, cells are harvested and transferredto 15 ml conical centrifuge tubes. After centrifugation for 10 min at200×g, supernatants are harvested and transferred to 1.5 ml Eppendorftubes. It may be noted that the cell pellet may be utilized for abiochemical evaluation of pre-IL-1β and/or mature IL-1β content incytosol extracts by western blotting or ELISA with pre-IL-1β specificantisera.

Isolation of Adherent Mononuclear cells

PBMC are isolated and prepared as described above. Media (1.0 ml) isfirst added to wells followed by 0.5 ml of the PBMC suspension. After aone hour incubation, plates are gently shaken and nonadherent cellsaspirated from each well. Wells are then gently washed three times with1.0 ml of media and final resuspended in 1.0 ml media. The enrichmentfor adherent cells generally yields 2.5-3.0×10⁵ cells per well. Theaddition of test compounds, LPS, cell incubation conditions andprocessing of supernatants proceeds as described above.

ELISA

We have used Quantikine kits (R&D Systems) for measurement of matureIL-1β. Assays are performed according to the manufacturer's directions.Mature IL-1β levels of about 1-3 ng/ml in both PBMC and adherentmononuclear cell positive controls are observed. ELISA assays areperformed on 1:5, 1:10 and 1:20 dilutions of supernatants fromLPS-positive controls to select the optimal dilution for supernatants inthe test panel.

The inhibitory potency of the compounds can be represented by an IC₅₀value, which is the concentration of inhibitor at which 50% of matureIL-1β is detected in the supernatant as compared to the positivecontrols.

The following K_(i) and IC₅₀ values were determined for compounds Athrough N using the indicated assays. Structures for compounds A throughN follow this table.

Compound K_(i) (μM), by indicated assay

    ______________________________________                                                K.sub.i (μM), by indicated assay:                                            UV-visible   Fluorescence                                                                            Cell                                         Compound  K.sub.i (μM)                                                                            K.sub.i (μM)                                                                         IC.sub.50 (μM)                            ______________________________________                                        A         5.5                    25.0                                         B         8.6                    20.0                                         C         10                     >30                                          D         4.7                                                                 E         3.2                                                                 F         0.15                   2-4                                          G         4.8                                                                 H         0.023        0.0047    6-11                                         I         0.0072       0.0052    2.6                                          J         0.012        0.0039    5-7                                          K         0.010        0.002     2-11                                         L         0.014                                                               M         0.15                                                                N         0.95                                                                ______________________________________                                    

Structures of compounds A through N ##STR122##

EXAMPLE 3

Compounds of Example 2 were synthesized as follows

H. N-(N-Acetyl-tyrosinyl-valinyl-pipecolyl)-3-amino-4-oxobutanoic acid

Step A.N-(N-tert-Butoxycarbonylpipecolyl)-4-amino-5-benzyloxy-2-oxotetrahydrofura

Reaction of N-tert-butoxycarbonylpipecolic acid (460 mg, 2.0 mmol) andN-allyloxycarbonyl-4-amino-5-benzyloxy-2-oxotetrahydrofuran (530 mg,1.82 mmol) was carried out by a method analogous to that reported byChapman (Bioorg. & Med. Chem. Lett. 1992, 2, 613-618.) to give 654 mg ofthe title compound.

¹ H NMR (500 MHz, CDCl₃ (existing as rotamers)) δ 7.35 (m, 5H), 6.88(br. s, 1H), 4.9-4.45(m, 4H), 3.95 (br. m, 2H), 3.06 (m, 1H), 2.9 (m,1H), 2.7 (br. m, 1H), 2.45 (m, 1H), 2.2 (m, 1H), 1.7-1.5 (m, 3H), 1.45(two s, 9H).

Step B. N-Pipecolyl-4-amino-5-benzyloxy-2-oxotetrahydrofuran

N-(N-tert-Butoxycarbonylpipecolyl)-4-amino-5-benzyloxy-2-oxo-tetrahydrofuran(654 mg) was dissolved in 15 ml of 25% trifluoroacetic acid indichloromethane and stirred at room temperature. The mixture wasconcentrated to give a gummy residue. The residue was dissolved indichloromethane and washed with 10% sodium bicarbonate. The organiclayer was dried over anhydrous sodium sulfate, filtered, andconcentrated to give 422 mg of the title compound as a beige solid.

¹ H NMR (500 MHz, CDCl₃) δ 7.38 (m, 5H) , 7.15 (d, 1H), 5.55 (d, 1H),4.95-4.8 (m, 1H), 4.78 (m, 1H), 4.65 (d, 1H), 4.45 (m, 1H), 3.2 (m,0.5H), 3.05 (m, 0.5H), 2.95 (m, 0.5H), 2.85 (m, 0.5H), 2.65 (m, 1H),2.55-2.38 (m, 1H), 1.95 (m, 1H), 1.8 (m, 1H), 1.6 (m, 2H), 1.38 (m, 2H).

Step C.N-(N-Acetyl-tyrosinyl-valinyl-pipecolyl)-4-amino-5-benzyloxy-2-oxotetrahydrofuran

N-Acetyl-tyrosinyl-valine (464 mg, 1.44 mmol) andN-Pipecolyl-4-amino-5-benzyloxy-2-oxotetrahydrofuran (412 mg, 1.3 mmol)were dissolved in 5 ml each of dimethylformamide and dichloromethane andcooled to 0° C. To the cooled solution was added 1-hydroxybenzotriazole(HOBT; 210 mg, 1.56 mmol) followed by the addition of1-(3-dimethylaminopropyl)-3-ethyl carbodiimide hydrochloride (EDC; 326mg, 1.7 mmol). After stirring for 18 hours, the mixture was diluted withethyl acetate and washed with water, 10% sodium hydrogen sulfate, 10%sodium bicarbonate, and water. The organic layer was concentrated togive a crude solid that was purified by flash chromatography (SiO₂)eluting with 94:6:1 (dichloromethane:isopropanol:pyridine) to give 370mg of the title compound.

¹ H NMR (500 MHz, CD₃ OD (existing as diastereomers as well asrotamers)) δ 7.35 (m, 5H), 7.05 (m, 2H), 6.68 (m, 2H), 5.65 & 5.25 (m,1H), 4.9-3.95 (m, 8H), 3.4-2.6 (m, 4H), 2.5-2.1 (m, 1H), 1.98 (s, 1H),1.9 (s, 1H), 1.85 (s, 1H), 1.8-1.6 (m, 2H), 1.55-1.3 (m, 4H), 0.95-0.85(m, 6H).

Step D. N-(N-Acetyl-tyrosinyl-valinyl-pipecolyl)-3-amino-4-oxobutanoicacid

To a solution of 100 mg ofN-(N-Acetyl-tyrosinyl-valinyl-pipecolyl)-4-amino-5-benzyloxy-2-oxotetrahydrofuranin 10 ml of methanol was added 60 mg of Pd(OH)₂ on carbon and themixture placed under an atmosphere of hydrogen via a balloon. Themixture was filtered through Celite and concentrated providing a whitesolid. This crude solid was dissolved in 2 ml of methanol and trituratedwith diethyl ether affording 26 mg of the title compound.

¹ H NMR (500 MHz, CD₃ OD(existing as diastereomers as well as rotamers))δ 7.1 (m, 2H), 6.7 (m, 2H), 5.2 (br. m, 1H), 4.8-3.6 (m, 6H), 3.2-2.5(m, 4H), 2.5-2.1 (m, 1H), 1.95 (three s, 3H), 1.9-1.3 (m, 6H), 1.1-0.7(m, 6H).

The following compounds were prepared by a method analogous to thatreported for H:

J.N-[N-Acetyl-tyrosinyl-valinyl-(4-hydroxyprolinyl)]-3-amino-4-oxobutanoicacid

Substitute N-tert-butoxycarbonyl-4-benzyloxyproline forN-tert-butoxycarbonylpipecolic acid.

L.N-[2-(N-Acetyl-tyrosinyl-valinyl)-(S)-1,2,3,4-tetrahydroisoguinoline-3-carbonyl]-3-amino-oxobutanoicacid

Substitute(S)-N-tert-butoxycarbonyl-1,2,3,4-tetrahydroisoquinoline-3-carboxylicacid for N-tert-butoxycarbonylpipecolic acid.

I.N-(N-Acetyl-tyrosinyl-valinyl-(4-phenoxyprolinyl))-3-amino-4-oxobutanoicacid

Step A. N-tert-Butoxycarbonyl-4-phenoxyproline methyl ester

To a cooled solution (0° C.) of N-tert-butoxy-cis-4-hydroxyproline (2-0g, 8.15 mmol), phenol (0.77 g, 8.15 mmol), and triphenylphosphine (2.14g, 8.15 mmol) in 20 ml of tetrahydrofuran was added diethylazodicarboxylate (1.4 ml, 9 mmol) dropwise over 30 minutes. The reactionwas stirred at room temperature for 16 hrs. then concentrated to give aviscous residue. The crude residue was purified by flash chromatography(SiO₂) eluting with 3:7 (ethyl acetate:hexane) to give 1.89 g of thetitle compound.

¹ H NMR (500 MHz, CDCl₃) δ 7.3 (m, 2H), 6.95 (m, 1H), 6.85 (d, 2H), 4.9(m br., 1H), 4.55-4.15 (m, 2H), 3.88-3.65 (m, 1H), 3.70 (s, 3H), 2.58(m, 1H), 2.22 (m, 1H), 1.4 (3×s, 9H).

Step B. 4-Phenoxyproline methyl ester hydrochloride

To a cooled solution (ice bath) ofN-tert-Butoxycarbonyl-4-phenoxyproline methyl ester (0.6 g) in 20 ml ofethyl acetate was bubbled anhydrous hydrogen chloride until saturated.The mixture was warmed to room temperature and stirred for 3 hrs. thenconcentrated to give 480 mg of the title compound.

¹ H NMR (500 MHz, CDCl₃) δ 7.22 (m,2H), 6.95 (m 1 H), 6.83 (m, 2H), 5.1(br., 1H), 4.6 (br. m, 1H), 4.06 (br. m, 1H), 3.75 (s, 3H), 3.55 (br. m,1H), 2.58 (m, 2H).

Step C. N-Acetyl-tyrosinyl-valinyl-(4-phenoxy)proline methyl ester

N-Acetyl-tyrosinyl-valine (0.524 g, 1.63 mmol) and 4-phenoxyprolinemethyl ester (0.381 g, 1.48 mmol) were dissolved in 4 ml each ofdimethylformamide and dichloromethane and cooled to 0° C. To the cooledsolution was added diisopropylethylamine (258 ul, 1.86 mmol), HOBT (0.24g, 1.78 mmol), and EDC (0.37 g, 1.92 mmol) and the reaction was stirredfor 18 hrs. The mixture was diluted with 400 ml of ethyl acetate andwashed with water, 10% sodium hydrogen sulfate, 10% sodium bicarbonate,and water. The organic layer was concentrated to give a residue that waspurified by flash chromatography (SiO₂) eluting with 94:6:1 (CH₂ Cl₂:i-PrOH:Pyridine) to afford 360 mg of the title compound.

¹ H NMR (500 MHz, CDCl₃ (existing as rotamers)) δ 7.3 (m, 2H), 7.05 (m,1H), 6.95 (d, 2H), 6.9-6.2 (4×d, 4H), 5.05 (br. s, 1H), 4.7-3.94 (m,5H),2.93 (m, 1H), 2.82(m, 1H), 2.65 (m, 1H), 2.2 (m, 1H), 2.05 (m, 1H), 1.95(s, 3H), 1.86, (m, 1H), 0.98 (d, 3H), 0.88 (d, 3H).

Step D. N-Acetyl-tyrosinyl-valinyl-(4-phenoxy)proline

Lithium hydroxide (57 mg, 1.37 mmol) was added to a solution ofN-Acetyl-tyrosinyl-valinyl-(4-phenoxy)proline methyl ester (360 mg,0.685 mmol) dissolved in 8 ml of tetrahydrofuran/water (1:1) and stirredat room temperature for 1 hour. The mixture was acidified with 10%hydrochloric acid giving a white precipitate that was collected to give175 mg of the title compound.

¹ H NMR (500 MHz, DMSO-d6) δ 9.2 (br. s, 1H), 8.05-7.95 (m, 2H), 7.3 (m,1H), 7.0-6.9 (m,4H), 6.65 (d, 2H), 4.42 (m, 1H), 4.35(m, 1H), 4.05-3.95(m, 2H), 3.3 (br. s, 2H), 2.75 (m, 1H), 2.55-2.38 (m, 2H), 2.2 (m, 1H),2.0 (m, 1H), 1.7 (s, 3H), 0.95 (d, 3H), 0.85 (d, 3H).

Step E.N-[N-Acetyl-tyrosinyl-valinyl-(4-phenoxy)prolinyl]-4-amino-5-benzyloxy-2-oxotetrahydrofuran

The title compound was prepared by the method reported for compound H,step A, by reaction of N-acetyl-tyrosinyl-valinyl-(4-phenoxy)proline andN-allyloxycarbonyl-4-amino-5-benzyloxytetrahydrofuran.

¹ H NMR (500 MHz, CDCl₃ (existing as a 1:1 diastereomer mixture of thehemiacetal)) δ 7.8-6.3 (m, 17H), 5.6 (d, 1H), 5.1-4.15 (m, 5H),4.15-3.75 (m, 2H), 2.95-2.15 (m, 5H), 2.15-1.95 (m, 1H), 1.9-1.85 (2×s,3H), 1.1-0.75 (m, 6H).

Step F.N-[N-Acetyl-tyrosinyl-valinyl-(4-phenoxy)prolinyl]-3-amino-4-oxobutanoicacid

The title compound was prepared by the hydrogenolysis procedure reportedfor compound H, step D.

¹ H NMR (500 MHz, CD₃ OD (existing as a 1:1 diastereomer mixture of thehemiacetal)) δ 7.25 (m, 2H), 7.10-6.85 (m, 5H), 6.65 (d, 2H), 5.1 (br.m, 1H), 4.65-4.05 (m, 5H), 4.0-3.40 (m, 2H), 2.95-2.35 (m, 5H), 2.25 (m,1H), 2.05 (m, 1H), 1.85 (s, 3H), 1.0 (d, 3H), 0.95 (d, 3H).

K.N-[N-Acetyl-tyrosinyl-valinyl-(4-benzyloxy)prolinyl]-3-amino-4-oxobutanoicacid

Step A. N-(N-Allyloxycarbonyl-4-benzyloxyprolinyl)-3-amino-4-oxobutanoicacid tert-butyl ester semicarbazone

The title compound was prepared by the reaction ofN-allyloxycarbonyl-4-benzyloxyproline and 3-amino-4-oxobutanoic acidtert-butyl ester semicarbazone (T. L. Graybill et. al., Abstracts ofpapers, 206th National Meeting of the American Chemical Society,Abstract MEDI-235. Chicago, Ill. (1993)) under similar peptide couplingconditions as reported above (compound H; Step C).

¹ H NMR (500 MHz, CDCl₃) δ 9.05 (br. s, 1H), 7.85 (br. m, 1H), 7.4-7.2(m, 5H), 7.15 (br. s, 1H), 6.55 (br. s, 1H), 5.9 (m, 1H), 5.1-4.9 (br.m, 2H), 4.65-4.4 (m, 4H), 4.2 (br. m, 1H), 3.75-3.5 (m, 2H), 2.75-2.55(m, 2H), 2.5 (br. m, 1H), 2.25 (br. m, 1H) 1.4 (s, 9H).

Step B.N-(N-Acetyl-tyrosinyl-valinyl-(4-benzyloxyprolinyl))-3-amino-4oxobutanoicacid tert-butyl ester semicarbazone

The title compound was prepared by reaction of N-acetyl-tyrosinyl-valineand N-(N-allyloxycarbonyl-4-benzyloxyprolinyl)-3-amino-4-oxobutanoicacid tert-butyl ester semicarbazone by reaction conditions reported forcompound H, step A.

¹ H NMR (500 MHz, CD₃ OD) δ 7.35-7.2 (m, 6H), 7.0 (d, 2H), 6.65(d, 2H),4.85 (m, 1H), 4.6-4.45 (m, 4H), 4.3 (br. m, 1H), 4.15 (m, 1H), 3.7 (m,1H), 2.95 (m, IH), 2.75-2.6 (m, 3H), 2.35 (m, 1H), 2.1 (m, 1H), 1.9 (s,3H), 1.4 (s, 9H), 0.95 (d, 3H), 0.90 (s, 3H).

Step C.N-(N-Acetyl-tyrosinyl-valinyl-(4-benzyloxyprolinyl))-3-amino-4oxobutanoicacid

N-(N-Acetyl-tyrosinyl-valinyl-(4-benzyloxyprolinyl))-3-amino-4-oxobutanoicacid tert-butyl ester semicarbazone (270 mg) was dissolved into 10 ml of25% trifluoroacetic acid in dichloromethane and stirred at roomtemperature for 3 hours. The mixture was concentrated to give a solidresidue. The residue was dissolved into a 10 ml mixture ofmethanol:acetic acid:37% formaldehyde (3:1:1) and stirred at roomtemperature for 1 hour. The mixture was concentrated and the resultingresidue purified by flash chromatography (SiO₂) eluting withdichloromethane/methanol/formic acid (100:5:0.5) to give 37 mg of thetitle compound.

¹ H NMR (500 MHz, CD₃ OD (existing as a 1:1 mixture of diastereomers ofthe hemiacetal)) δ 7.4-7.25 (m, 5H), 7.0 (d, 2H), 6.65 (d, 2H),4.65-4.05 (m, 7H), 3.75-3.4 (m, 2H), 3.05-2.3 (m, 5H), 2.2-1.95 (m, 2H),1.90 (s, 3H), 1.0 (d, 3H), 0.95 (d, 3H).

EXAMPLE 4

We obtained inhibition constants (K_(i)) and IC₅₀ values for severalcompounds of this invention using enzyme assays with UV-visiblesubstrate and cell assays as described in Example 2. The following K_(i)and IC₅₀ values were determined for compounds 7a, 7b, 20a-d, 21c-f, 22e,25, 28, 33a-c, 36a, 36b, 39, 43, 47a, 47b, 54a-l, 63, 69a, 69b, 84a and84b using the indicated assays. Corresponding lettered compounddesignations are indicated parenthetically. The compound structures areshown in Examples 2 and 5.

    ______________________________________                                                     Assay                                                                           UV-visible                                                                              Cell                                                 Compound       K.sub.i (μM)                                                                         IC.sub.50 (μM)                                    ______________________________________                                         7a            35                                                              7b            1.2                                                            20a (=E)       3.2                                                            20b            0.85      16.4                                                 20c (=N)       0.95                                                           20d            0.1       6.2                                                  21c            0.64                                                           21d            0.24      4.8                                                  21e            0.22      2.9                                                  21f            0.17      2.9                                                  22e            0.19                                                           25             6.2                                                            28             12.0                                                           33a (=A)       5.5       25.0                                                 33b (=C)       10.0      >30.0                                                33c (=B)       8.6       20.0                                                 36a (=D)       4.7                                                            36b            0.8       17.0                                                 39             2.5                                                            43             20.0                                                           47a            0.019     2.1                                                  47b            0.027     1.8                                                  54a (=F)       0.15      2.7                                                  54b (=M)       0.15      9.1                                                  54c            1.2       >19.0                                                54d            1.0                                                            54e            3.5                                                            54f            0.9                                                            54g (=G)       4.8                            >20.0                           54h            0.97                                                           54i            0.054     2.4                                                  54j            0.28                                                           54k            0.085                                                          54l            0.215     7.0                                                  63 (=O)        0.85      4.1                                                  69a (=R)       0.011     0.735                                                69b (=S)       0.050     0.745                                                84a (=V)       0.100     3.3                                                  84b (=W)       0.019     0.50                                                 ______________________________________                                    

EXAMPLE 5

Compounds of Example 4 were synthesized as follows: ##STR123##

3-Benzoylamino-4-oxo-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-6-carboxylicacid methyl ester (3). A mixture of(4S)-2-amino-1-pyrroline-5-carboxylic acid ethyl ester hydrochloride (1,0.44 g, 2.38 mmol; prepared in an analogous fashion as the methyl esteras described by Lee and Lown, J. Org. Chem., 52, 5717-21 (1987));4-ethoxymethylene-2-phenyl-2-oxazolin-5-one (2, 0.50 g, 2.31 mmol) andsodium methoxide (0.12 g, 2.22 mmol) in ethanol (10 ml) was refluxed for2 h. The reaction was allowed to cool to room temperature andconcentrated in vacuo. The residue was suspended in water and 1Nsulfuric acid was added until pH 1 was reached. The aqueous mixture wasextracted with dichloromethane, the organic layer was separated andconcentrated in vacuo to yield 0.6 g of a orange solid. Chromatography(flash, SiO₂, 60% ethyl acetate/hexane increased to 100% ethyl acetatestepwise gradient, then 10% methanol/dichloromethane) to give 0.5 g ofan orange solid. A mixture of the orange solid and potassium cyanide(0.03 g, 0.5 mmol) in methanol (10 ml) was refluxed overnight. Thecooled reaction was concentrated in vacuo to give a yellow solid.Chromatography (flash, SiO₂, 40% ethyl acetate/hexane to 100% ethylacetate stepwise gradient) afforded 0.22 g (31.6%) of the titlecompound: ¹ H NMR (d₆ -DMSO) δ 2.25 (m, 1H), 2.65 (m, 1H), 3.15 (m, 2H),3.75 (8, 3H), 5.15 (dd, 1H), 7.5 (t, 2H), 7.6 (t, 1H), 7.95 (d, 2H), 8.6(s, 1H) , 9.5 (s, 1H)

(3S)-[(3-benzoylamino-4-oxo-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-6-carbonyl)-amino]-4-oxo-butanoicacid tert-butyl ester semicarbazone (5a and 5b). A mixture of3-benzoylamino-4-oxo-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-6-carboxylicacid ethyl ester (3, 0.22 g 0.70 mmol) and lithium hydroxide hydrate(0.032 g, 0.76 mmol) in methanol (5 ml) and tetrahydrofuran (5 ml) andwas stirred 18 h at room temperature. The reaction was concentrated togive3-benzoylamino-4-oxo-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pryrimidine-6-carboxylicacid lithium salt (4) as a white solid. This was used without furtherpurification in the subsequent reaction.

A 0° C. mixture of (3S)-amino-4-oxo-butanoic acid tert-butyl estersemicarbazone (0.163 g, 0.71 mmol; Graybill et al., Int. J. ProteinRes., 44, pp. 173-82 (1994)) and3-benzoylamino-4-oxo-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-6-carboxylicacid lithium salt (4) in dimethylformamide (5 ml) and dichloromethane (5ml) was treated with hydroxybenzotriazole (0.104 g, 0.77 mmol) and1-(3-dimethylaminopropyl)-3-ethyl carbodiimide hydrogen chloride (0.148g. 0.37 mmol). The reaction was allowed to warm to room temperature andstirred 18 hr. The reaction was poured onto water (50 ml) and extractedwith ethyl acetate (2×50 mL). The combined organic layers were washedwith aqueous 1M sodium hydrogen sulfate solution, dilute aqueous sodiumhydrogen carbonate (50 mL) and saturated aqueous sodium chloride. Theorganic layer was concentrated in vacuo to yield 0.43 g of a yellowsolid. Chromatography (flash, SiO₂, ammoniumhydroxide/methanol/dichloromethane (1:1:99 to 1:10:90 stepwisegradient)) gave 0.11 g (30.9%) of the higher Rf diastereomer (5a): ¹ HNMR (CD₃ OD) δ 1.45 (s, 9H), 2.29-2.35 (m, 1H), 2.6-2.7 (m, 2H), 2.8(dd, 1H), 3.1-3.15 (m, 1H), 3.2-3.3 (m, 1H), 4.9-4.95 (m, 1H), 5.2 (dd,1H), 7.25 (d, 1H), 7.5-7.55 (m, 2H), 7.55-7.6 (m, 1H), 7.95 (d, 2H), 8.9(s, 1H) and 0.11 g (30.9%) of the lower Rf diastereomer (5b): ¹ H NMR(CD₃ OD) δ 1.45 (s,9H), 2.3-2.4 (m, 1H), 2.6-2.7 (m, 1H), 2.7-2.8 (m,2H), 3.1-3.15 (m, 1H), 3.2-3.3 (m, 1H), 4.85-4.95 (m, 1H), 5.15 (dd,1H), 7.25 (d, 1H), 7.55 (t, 2H), 7.6 (t, 1H), 7.95 (d, 2H), 8.9 (s, 1H).Diastereomer 5a and diastereomer 5b were taken on separately.

(3S)-[(3-benzoylamino-4-oxo-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-6-carbonyl)-amino]-4-oxo-butanoicacid (7a). A suspension of(3S)-[(3-benzoylamino-4-oxo-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-6-carbonyl)-amino]-4-oxo-butanoicacid tert-butyl ester semicarbazone (5a, 0.11 g, 0.22 mmol) indichloromethane (7.5 ml) and trifluoroacetic acid (2.5 ml) was stirredfor 5 h. The reaction was concentrated in vacuo, the residue was takenup in dichloromethane, concentrated in vacuo, suspended in toluene andconcentrated in vacuo to give 0.07 g of(3S)-[(3-benzoylamino-4-oxo-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-6-carbonyl)-amino]-4-oxo-butanoicacid semicarbazone (6a) as a white solid. The solid was suspended in amixture of 37% aqueous formaldehyde/acetic acid/methanol (1:1:5) andstirred at room temperature for 18 hr. The reaction was concentrated invacuo, the residue was suspended in acetonitrile and concentrated invacuo to give 0.1 g of a white solid. Chromatography (HPLC, reversephase C18, 1% to 75% acetonitrile/water (buffered with 0.1%trifluoroacetic acid) gradient elution) to give 0.05 g (60%) of 7a as awhite solid: RT=7.9 min (HPLC, C18 reverse phase, 1 to 100%acetonitrile/water (0.1% trifluoroacetic acid buffer); 20 min gradientelution); ¹ H NMR (CD₃ OD (existing as a 1:1 mixture of anomers of thehemi-acyloxy acetal form)) δ 2.25-2.4 (m, 1H), 2.45-2.8 (m, 4H),3.05-3.15 (m, 1H), 4.25-4.35 (m, 1H), 4.55-4.6 (m, 1H), 5.1-5.2 (m, 1H),7.45-7.65 (m, 3H), 7.9-8.0 (m, 2H), 8.9 (s, 1H).

(3S)-[(3-benzoylamino-4-oxo-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-6-carbonyl)-amino]-4-oxo-butanoicacid (7b) was prepared as described for diastereomer 7a to give 0.03 g(35%) of 7b as a white solid: RT=8.1 min (HPLC, C18 reverse phase, 1 to100% acetonitrile/water (0.1% trifluoroacetic acid buffer); 20 mingradient elution); ¹ H NMR (d₆ -DMSO (existing as a 1:1 mixture ofanomers of the hemi-acyloxy acetal form)) δ 2.1-2.2 (m, 1H), 2.4 (d,1H), 2.7-2.8 (m, 1H), 3.0-3.2 (m, 3H), 5.0 (dd, 1H), 5.1-5.2 (m, 1H),5.5 (s, 1H), 5.7-5.8 (m, 1H), 7.55 (t, 2H), 7.67 (t, 1H), 7.95 (d, 2H),8.55 (s, 1H), 9.0-9.15 (m, 1H), 9.4-9.5 (m, 1H). ##STR124##

Imidazole-2-carboxylic acids 13 were prepared using modifications ofdescribed procedures (Yamanaka et al., Chem. Pharm. Bull., 31, pp.4549-53 (1983)); Suzuki et al., J. Org. Chem., 38, pp. 3571-75 (1973));and Oliver et al. (J. Org. Chem., 38, pp. 1437-38 (1973)).

Imidazole-2-carboxylic acid (13a) was prepared according to Curtis andBrown, J. Org. Chem., 45, pp. 4038-40 (1980).

4-Benzylimidazole-2-carboxylic acid (13b), was isolated as an off-whitesolid: mp. 153-155° C.; IR (KBr) 3026-2624, 1630, 1515, 1498, 1438,1405; ¹ H NMR(d₆ -DMSO) δ 7.31 (5H, m), 7.14 (1H, s), 3.95 (2H, s).

4-(2-Phenylethyl)imidazole-2-carboxylic acid (13c), was isolated as apale yellow solid: mp. 151-153° C.; IR (KBr) 3054-2617, 1637, 1497,1376; ¹ H NMR(d₆ -DMSO) δ 7.27 (5H, m), 7.11 (1H, s), 2.92 (4H, s).

4-(3-Phenylpropyl)imidazole-2-carboxylic acid (13d), was isolated as apale yellow solid: mp. 148-150° C.; IR (KBr) 3020-2615, 1636, 1509,1498, 1383; ¹ H NMR(d₆ -DMSO) δ 7.35-7.22 (5H, m), 7.01 (1H, s), 2.62(4H, m), 1.94 (2H, m).

4-[3-(4-Methoxyphenyl)propyl]imidazole-2-carboxylic acid (13e), wasisolated as a white crystalline solid: mp. 155-156° C. (decomp.); IR(KBr) 3300-2300, 1633, 1513, 1376, 1244; ¹ H NMR(d₆ -DMSO) δ 9.50-7.50(2H, bs), 7.15 (1H, s), 7.11 (2H, d, J=8.5), 6.84 (2H, d, J=8.5), 3.71(3H, s), 2.60-2.50 (4H, m), 1.86 (2H, m). Anal. Calcd for C₁₄ H₁₆ N₂ O₃: C, 64.60; H, 6.20; N, 10.76. Found: C, 64.45; H, 6.21; N, 10.70.

4-[3-(4-Hydroxyphenyl)propyl]imdazole-2-carboxylic acid (13f). Asolution of the ethyl ester of 13e (1.15 g, 4.0 mmol) in drydichloromethane (50 ml) was treated with boron tribromide (16 ml, 1.0 Msolution in CH₂ Cl₂, 16.0 mmol) at 0° C. After 15 min at 0° C., themixture was warmed to 25° C. and stirred for 16 h. The reaction mixturewas cooled in an ice bath and quenched with a dropwise addition of water(20 ml). The resulting mixture was briefly stirred at 25° C. thenfiltered. The filtrate was carefully neutralised by the addition ofsolid NaHCO₃ to afford 13f (700 mg, 71%) as a white solid: m.p. 186-187°C. (decomp.) (recrystallised from MeOH); IR (KBr) 3500-2400, 2935, 1640,1516, 1396, 1232; ¹ H NMR(d₆ -DMSO) δ 9.83 (3H, bs), 7.16 (1H, s), 6.98(2H, d, J=8.2), 6.66 (2H, d, J=8.2), 2.60-2.40 (4H, m), 1.84 (2H, m).Anal. Calcd for C₁₃ H₁₄ N₂ O₃ : C, 63.40; H, 5.73; N, 11.38. Found: C,62.96; H, 5.70; N, 11.27.

(2R,S, 3S) N²-Tert-butoxycarbonyl-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-alaninamide(14). Tri-n-butyl tin hydride (4.0 ml, 14.9 mmol) was added dropwise toa solution of (2R,S, 3S) 3-(N-allyloxycarbonyl)amino-2-benzyloxy-5-oxotetrahydrofuran (Chapman, Biorg. Med. Chem.Lett., 2, pp. 613-18 (1992); (2.91 g, 10 mmol)),N-tert-butoxycarbonyl-L-alanine (2.08 g, 11 mmol) andbis(triphenylphosphine)palladium (II) chloride (150 mg) indichloromethane (75 ml) until the colour of the solution turned darkorange. Hydroxybenzotriazole (2.70 g, 20 mmol) was added, and themixture cooled to 0° C. 1-(3-dimethylamino-propyl)-3-ethylcarbodiimidehydrochloride (2.30 g, 12 mmol) was added then the mixture was allowedto warm slowly to room temperature during 4 h. The mixture was dilutedwith ethyl acetate (250 ml) and washed with 1N hydrochloric acid (3×150ml), saturated aqueous sodium bicarbonate (3×150 ml) and brine (2×150ml), then dried (MgSO₄), filtered and concentrated. The crude productwas purified by column chromatography (50-70% ethyl acetate/hexane) toafford 3.17 g (84%) of a mixture of diastereomers. Recrystallization(ethyl acetate-hexane) gave colorless crystals: mp. 132-145° C.; IR(KBr) 3357, 3345, 1781, 1688, 1661, 1535, 1517, 1165; ¹ H NMR(d₆ -DMSO)δ 8.49 (d, J=6.8), 8.23 (d, J=7.4), 7.40 (5H, m), 7.01 (1H, m), 5.68 (d,J=5.0), 4.75 (m), 4.31 (m), 3.97 (1H, m), 2.82 (m), 3.11 (m), 2.82 (m),2.59 (m), 2.45 (m), 1.40 (9H, s), 1.20 (d, J=7.2), 1.16 (d, J=7.2).Anal. Calcd for C₁₉ H₂₆ N₂ O₆ : C, 60.31; H, 6.92; N, 7.40. Found C,60.30; H, 6.91; N, 7.38.

(2R, S, 3S)tert-Butoxycarbonyl-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-prolinamide(15), was prepared by the method described for 14 to afford 1.64 g (81%)of a colorless glass. IR (KBr) 3317, 2978, 1797, 1697, 1670, 1546, 1400,1366, 1164, 1121; ¹ H NMR(CDCl₃) δ 7.68 (1H, brm), 7.35 (5H, m); 5.53(d, J=5.2), 5.43 (s), 4.93-4.61 (m), 4.44 (m), 4.25 (brm), 3.39 (2H,brm), 3.10-2.81 (1H, m), 2.44 (1H, m), 2.32 (brm), 1.88 (brm), 1.67(brm), 1.42 (9H, s).

(2R,S, 3S)N-(N-tert-Butoxycarbonyl-(4(R)-phenoxy-L-prolinyl)-3-amino-2-benzyloxy-5-oxotetrahydrofuran(16) was prepared by the method described for 14 to afford 530 mg (84%)of a colorless amorphous solid: ¹ H NMR (CDCl₃) δ 7.65 (1H, m), 7.4-7.2(7 H, m), 6.95 (1H, m), 6.85 (1H, m), 5.55(1H, d), 4.95 (1H, d), 4.8-4.7(1H, brm), 4.65 (1H, d), 4.55-4.45 (1H, brm), 4.4-4.3 (0.5H, brm),3.95-3.85 (0.5H, brm), 3.75-3.58 (2H, m), 2.95-2.8 (1H, m), 2.7-2.55(1H, m), 2.54-2.4 (1H, m), 2.35-2.2 (1H, m), 1.4 (9H,s).

(2R,S, 3S) N²-[4-(3-Phenylpropyl)imidazole-2-carbonyl]-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-alaninamide(17d). Trifluoroacetic acid (7 ml) was added to a solution of (2R,S, 3S)N²-tert-butoxycarbonyl-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-alaninamide(14) (1.00 g, 2.64 mmol) in dichloromethane (7 ml) at 0° C. The mixturewas stirred at 0° C. for 75 min. The mixture was concentrated, and theresidue treated with diethyl ether then the ether was removed undervacuum. This procedure was repeated twice to yield a pale yellow glass.The solid was dissolved in DMF (20 ml). Diisopropylethylamine (1.38 ml,7.92 mmol) followed by 4-(3-phenylpropyl) imidazole-2-carboxylic acid(13d) (0.67 g, 290 mmol), 1-(3-dimethylaminopropyl)-3-ethyl carbodiimidehydrochloride (0.56 g, 2.90 mmol) and hydroxybenzotriazole (0.71 g, 5.28mmol) were then added to this solution. The mixture was stirred at roomtemperature for 20 h then poured into brine. The mixture was extractedwith ethyl acetate (3×50 ml). The combined organic extracts were washedwith saturated aqueous sodium bicarbonate (2×100 ml) then brine (2×100ml), dried (MgSO₄), filtered and concentrated. The residue was purifiedby column chromatography (ethyl acetate) to afford 0.99 g (76%) of 17das a mixture of diastereomers: IR (KBr) 3293, 3064, 2937, 1793, 1650,1530, 1451, 1446, 1119; ¹ H NMR (CDCl₃) δ 7.96 (brm), 7.62 (brd),7.36-7.10 (10H, m), 6.88 (s), 6.86 (s), 5.53 (d, J=5.2), 5.48 (s),4.87-4.52 (4H, m), 3.11-2.38 (2H, m), 2.65 (4H, m), 1.99 (2H, m), 1.47(d, J=6.9), 1.46 (d, J=7.0).

The following compounds were prepared in a similar manner:

(2R, S, 3S) N²-(Imidazole-2-carbonyl)-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-alaninamide(17a), was isolated (74%) as a pale yellow solid: IR (KBr) 3289, 3056,2937, 1793, 1664, 1642, 1528, 1453, 1440, 1124; ¹ H NMR (d₆ -DMSO) δ13.13 (1H, brs), 8.67 (d, J=7.0), 8.48 (d, J=7.8), 8.29 (d, J=6.8), 8.25(d, J=7.6), 7.40-7.34 (6H, m), 7.11 (1H, s), 5.69 (d, J=5.0), 5.49 (d,J=0.8), 4.85-4.31 (4H, m), 3.19-2.42 (2H, m), 1.38 (d, J=7.4), 1.34 (d,J=7.4).

(2R,S, 3S) N²-(4-Benzylimidazole-2-carbonyl)-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-alaninamide(17b), was isolated (75%) as a pale yellow glass: IR (KBr) 3294, 3031,2937, 1792, 1650, 1530, 1453, 1444, 1119; ¹ H NMR(CDCl₃) δ 7.99 (brm),7.75 (brd), 7.36-7.11 (10H, m), 6.81 (1H, s), 5.51, 5.45 (d, s, J=5.3),4.85-4.47 (4H, m), 3.95 (2H, s), 3.04-2.72 (1H, m), 2.48-2.35 (1H, m),1.44 (d, J=6.9), 1.43 (d, J=7.1).

(2R,S, 3S)N2-[4-(2-Phenylethyl)imidazole-2-carbonyl]-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-alaninamide(17c), was isolated (79%) as a pale yellow glass: IR (KBr) 3292, 3029,2936, 1793, 1650, 1530, 1453, 1444, 1119; ¹ H NMR(CDCl₃) δ 8.06 (brm),7.70 (brs), 7.39-7.15 (10H, m), 6.82 (s), 6.81 (s), 5.53 (d, J=5.2),5.48 (s), 4.87-4.53 (4H, m), 2.95 (4H, m), 3.11-2.37 (2H, m), 1.48 (d,J=5.6), 1.45 (d, J=6.7).

(2R,S, 3S)1-[4-(2-Phenylethyl)imidazole-2-carbonyl]-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-prolinamide(18c), was isolated (79%) as a pale yellow glass: IR (CH₂ Cl₂) 3422,2959, 1795, 1685, 1611, 1497, 1116; ¹ H NMR(d₆ -DMSO) δ 12.78-12.59 (1H,m), 8.61-8.34 (1H, m), 7.39-7.22 (10H, m), 6.99-6.61 (1H, m), 5.71-5.26(1H, m), 4.85-4.02 (4H, m), 3.63 (1H, m), 3.18-1.74 (11H, m)

(2R,S, 3S)1-[4-(3-Phenylpropyl)imidazole-2-carbonyl]-N-(tetrahydro-2-benzyl-oxy-5-oxo-3-furanyl)-L-prolinamide(18d), was isolated (87%) as a colorless glass: IR (CH₂ Cl₂) 3422, 3214,2945, 1794, 1685, 1604, 1496, 1117; ¹ H NMR(d₆ -DMSO) δ 12.71 (1H, brm),8.61-8.34 (1H, m), 7.45-7.18 (10H, m), 7.05-6.64 (1H, m), 5.70-5.28 (1H,m), 4.85-4.02 (4H, m), 3.62 (1H, m) 3.18-1.71 (13H, m).

(2R,S, 3S)1-{4-[3-(4-Methoxyphenyl)propyl]imidazole-2-carbonyl}-N-(tetra-hydro-2-benzyloxy-5-oxo-3-furanyl)-L-prolinamide(18e), was isolated (72%) as a white glassy solid: mp. 62-65° C.; IR(KBr) 3213, 2937, 1793, 1680, 1606, 1606, 1512, 1245; ¹ H NMR(d₆ -DMSO)δ 12.71, 12.67, 12.58 (1H, 3×bs), 8.60-8.30 (1H, m), 7.40-7.20 (5H, m),7.15-6.55 (5H, m), 5.66-5.20 (1H, m), 4.81-4.59 (2H, m), 4.55-4.05 (2H,m), 3.71 (3H, s), 3.65-3.45 (1H, m), 3.15-1.50 (13H, m). FABSMS m/e 547(M⁺, 100%), 439, 412, 340, 312, 243, 177, 154.

(2R,S, 3S)1-{4-[3-(4-Hydroxyphenyl)propyl]imidazole-2-carbonyl}-N-(tetra-hydro-2-benzyloxy-5-oxo-3-furanyl)-L-prolinamide(18f), was isolated (70%) as a light yellow glassy solid: mp. 86-90° C.;IR (KBr) 3298, 1790, 1669, 1606, 1515, 1242; ¹ H NMR(d₆ -DMSO) δ 12.66,12.56 (1H, 2×bs), 9.14 (1H, s), 8.57-8.30 (1H, m), 7.36-7.30 (5H, m)),7.02-6.83 (3H, m), 6.70-6.57 (2H, m ), 5.65-5.28 (1H, m), 4.80-4.49 (2H,m), 4.50-4.05 (2H, m), 3.65-3.45 (1H, m), 3.15-1.55 (13H, m). FABMS m/e533 (M⁺, 100%), 425, 298, 229, 176, 154.

1-{5-[3-(4-Methoxyphenyl)propyl]-1H-imidazole-2-carbonyl}-4(R)-phenoxypyrrolidine-2(S)-carbonyl-(tetrahydro-2(R,S)-benzyloxy-5-oxofuran-3(S)-yl)amide(19e) was isolated (77%) as a clear colorless amorphous solid. ¹ H NMR(CDCl₃) δ 9.95-9.75 (1H, m), 7.95 (1H, brs), 7.40-7.2 (7H, m), 7.2-6.78(7H, m), 5.65-5.6 (1H, m), 5.55-5.45 (1H, m), 5.3-5.2 (1H,m), 5.15-5.0(1H, m), 4.95-4.75 (1H, m), 4.7-4.6 (1H, m), 4.5-4.4 (1H, m), 4.35-4.25(1H, m), 3.8 (3H, s), 3.05-1.75 (10H, m).

(3S)3-{N-[4-(3-Phenylpropyl)imidazole-2-carbonyl]-L-alaninyl}amino-4-oxo-butanoicacid (20d). A mixture of (2R,S, 3S) N²-[4-(3-Phenylpropyl)imidazole-2-carbonyl]-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-alaninamide(0.93 g, 1.90 mmol) and 10% palladium on activated carbon (0.93 g) inmethanol (100 ml) was stirred under a hydrogen atmosphere for 5 h. Theresulting mixture was filtered and concentrated to yield a colorlessglass. Recrystallization from methanol-diethyl ether afforded 401 mg(53%) of 20d as a colorless solid: mp. 94-96° C.; [α]_(D) ²⁷ +16.40 (c0.5, MeOH); IR (KBr) 3300, 3287, 1786, 1732, 1659, 1651, 1532, 1451; ¹ HNMR(CD₃ OD) δ 7.19 (5H, m), 6.91 (1H, s), 4.60-4.46 (2H, m), 4.27 (1H,m), 2.63 (4H, m), 2.75-2.40 (2H, m), 1.96 (2H, m), 1.44 (3H, d, J=7.0).

The following compounds were prepared in a similar manner:

(3S) 3-[N-(imidazole-2-carbonyl)-L-alaninyl]amino-4-oxobutanoic acid(20a; E), was isolated (83%) as a colorless solid: mp. 115° C.; [α]_(D)²⁵ +4.4° (c 0.5, MeOH); IR (KBr) 3303, 1782, 1658, 1650, 1563, 1521,1454; 1H NMR(CD₃ OD) δ 7.18 (2H, s) , 4.55 (2H, m) , 4.27 (1H, m), 2.56(2H, m), 1.45 (d, J=7.1), 1.44 (d, J=7.0).

(3S) 3-[N-(4-Benzylimidazole-2-carbonyl)-L-alaninyl]amino-4-oxobutanoicacid (20b), was isolated (56%) as a colorless solid: mp. 113-115° C.;[α]_(D) ²⁹ +18.2° (c 0.5 MeOH). IR (KBr) 3301, 3288, 1783, 1727, 1650,1531, 1452; ¹ H NMR(CD₃ OD) δ 7.25 (5H, m), 6.90 (1H, s), 4.59-4.45 (2H,m), 4.26 (1H, m), 3.95 (2H, s), 2.74-2.39 (2H, m), 1.42 (3H, d, J=7.0).Anal. Calcd for C₁₈ H₂₀ N₄ O₅ : C, 56.69; H, 5.55; N, 14.69. Found: C,57.06; H, 5.54; N, 14.41.

(3S)3-{N-[4-(2-Phenylethyl)imidazole-2-carbonyl]-L-alaninyl}amino-4-oxobutanoicacid (20c; N), was isolated (53%) as a colorless solid: mp. 102-104° C.;[α]_(D) ²⁷ +13.7° (c 0.5, MeOH); IR (KBr) 3299, 3289, 1785, 1732, 1650,1531, 1452; ¹ H NMR(CD₃ OD) δ 7.20 (5H, m), 6.82 (1H, s), 4.60-4.46 (2H,m), 4.29 (1H, m), 2.92 (4H, s), 2.76-2.41 (2H, m), 1.44 (3H, 2×d,J=7.1). Anal. Calcd for C₁₉ H₂₂ N₄ O₅ H₂ O: C, 56.43; H, 5.98; N, 13.85.Found: C, 56.65; H, 5.84; N, 13.91.

(3S)3{N-[4-(2-Phenylethyl)imidazole-2-carbonyl]-L-prolinyl}amino-4-oxobutanoicacid (21c), was isolated (85%) as a colorless glass: mp. 101-103° C.(methanol-diethyl ether); [α]_(D) ²⁷ -63.8° (c 0.25, MeOH); IR (KBr)3275, 1784, 1728, 1664, 1606, 1498, 1429; ¹ H NMR(CD₃ OD) δ 7.24 (5H,m), 6.83 (s), 6.79 (s), 4.58-4.14 (3H, m), 3.69 (1H, m), 2.93 (4H, brs),2.75-1.99 (6H, m). Anal. Calcd for C₂₁ H₂₄ N₄ O₅ H₂ O: C, 58.60; H,6.09; N, 13.02. Found: C, 58.34; H, 5.96; N, 12.67.

(3S)3-{N-[4-(3-Phenylpropyl)imidazole-2-carbonyl]-L-prolinyl}amino-4-oxo-butanoicacid (21d), was isolated(81%) as a colorless glass: mp. 91-94° C.;(methanol-diethyl ether) ; [α]_(D) ²⁵ -68° (c 0.25, MeOH); IR (KBr)3277, 2939, 1784, 1727, 1662, 1606, 1498, 1429; ¹ H NMR(CD₃ OD) δ7.29-7.16 (5H, m), 6.92 (s), 6.86 (s), 4.58-4.16 (3H, m), 3.71 (1H, m),2.75-1.92 (13H, m). Anal. Calcd for C₂₂ H₂₆ N₄ O₅ H₂ O: C, 59.45; H,6.35; N, 12.60. Found: C, 59.75; H, 6.21; N, 12.41.

(3S)3-{N-[4-[3-(4-Methoxyphenyl)propyl]imidazole-2-carbonyl]-L-prolinyl}amino-4-oxobutanoicacid (21e), was isolated (65%) as a white glassy solid: mp. 101-105° C.;[α]_(D) ²³ -60.6 (c 0.05, MeOH); IR (KBr) 3231, 1784, 1726, 1611, 1512,1245; ¹ H NMR(CD₃ OD) δ 7.09 (2H, d, J=8.6), 6.92, 6.85 (1H, 2×s), 6.81(2H, d, J=8.6), 5.45-5.30 (1H, m), 4.64-4.46 (1H, m), 4.28-4.10 (2H, m),3.75 (3H, s), 3.74-3.66 (1H, m), 2.67-1.84 (13H, m). Anal. Calcd for C₂₃H₂₈ N₄ O₆ H₂ O: C, 58.22; H, 6.37; N, 11.81. Found: C, 58.39; H, 6.34;N, 11.45; FABMS m/e 457 (M⁺), 405, 312, 243, 215, 176, 154 (100%).

(3S)3-{N-[4-[3-(4-Hydroxyphenyl)propyl]imidazole-2-carbonyl]-L-prolinyl}amino-4-oxobutanoicacid (21f), was isolated (43%) as a white glassy solid: mp. 114-118° C.;[α]_(D) ²⁵ -55.7° (c 0.05, MeOH); IR (KBr) 3288, 2935, 1780, 1715, 1662,1610, 1515, 1441; ¹ H NMR(CD₃ OD) δ 6.99 (2H, d, J=8.5), 6.91, 6.85 (1H,2×s), 6.68 (2H, d, J=8.5), 5.45-5.30 (1H, m), 4.60-4.47 (1H, m),4.30-4.10 (2H, m), 3.80-3.55 (1H, m), 2.70-1.80 (13H, m). Anal. Calcdfor C₂₂ H₂₆ N₄ O₆ H₂ O: C, 57.38; H, 6.13; N, 12.17. Found: C, 57.68; H,6.25; N, 11.66. FABMS m/e 443 (M⁺), 298, 229, 154 (100%).

3(S)-[(1-{5-[3-(4-Methoxyphenyl)propyl]-1H-imidazole-2-carbonyl}-4(R)-phenoxypyrrolidine-2(S)-carbonyl)amino]-4-oxobutanoic acid (22e) was isolated(43%) as a beige solid: ¹ H NMR (CD₃ OD) δ 7.35-7.2 (3H,m), 7.15-7.0(2H,m), 6.98-6.85 (3H, m), 6.83-6.77 (2H,d), 5.4-5.1 (1H,m), 4.65-4.5(1H,m), 4.35-4.2 (2H,m), 4.15-3.90 (1H,m), 3.78 (3H, s), 3.62-3.48 (1H,m), 2.78-2.25 (8H, m), 2.02-1.9 (2H,m). ##STR125##

{Phenylethyl-[5-(3-propyl)-1H-imidazole-2-carbonyl]amino}acetic acidtert-butyl ester (23). A 0° C. solution of4-(3-phenylpropyl)-imidazole-2-carboxylic (13d) (150 mg, 0.65 mmol) andN-(2-phenylethyl)glycine tert-butyl ester (140 mg, 0.59 mmol) in 5 ml ofanhydrous dimethylformamide was treated with diisopropylethylamine (154μl, 0.89 mmol), hydroxy-benzotriazole (160 mg, 1.18 mmol), and1-(3-dimethylaminopropyl)-3-ethyl carbodiimide hydrochloride (136 mg,0.71 mmol). After stirring for 36 h, the reaction was poured ontosaturated aqueous sodium chloride and extracted with ethyl acetate (3×50ml) The combined organic extracts were washed twice with saturatedaqueous sodium bicarbonate (2×) and saturated aqueous sodium chloride(1×), dried (Na₂ SO₄), filtered, and concentrated in vacuo to give abrown oil. Chromatography (flash, SiO₂, 30% ethyl acetate/hexane) togive 160 mg (61%) of 23 as a white solid: ¹ H NMR (CDCl₃) δ 7.38-7.14(10H, m), 6.85-6.8 (1H, m), 4.84-4.76 (1H, d), 4.5-4.42 (1H, m),4.07-4.0 (1H, d), 3.78-3.72 (1H, m), 3.12-2.94 (2H, 2×m), 2.75-2.55 (4H,m), 2.1-1.95 (2H,m), 1.5-1.45 (9H, 3×s).

(3S)-(2-Phenylethyl-[5-(3-phenylpropyl)-1H-imidazole-2-carbonyl]amino}acetylamino) 4-oxobutanoic acid tert-butyl ester semicarbazone (24). The ester23 (160 mg, 0.357 mmol) was treated with 25% trifluoroaceticacid/dichloromethane (7 ml) for 4 h. The reaction was concentrated invacuo to afford 180 mg of the acid. The acid (180 mg, 0.357 mmol) wascoupled to (3S)-3-amino-4-oxobutanoic acid tert-butyl estersemicarbazone (161 mg, 0.357 mmol) as describe for the preparation of 5aand 5b to give 86 mg (33%) of 24 (one diastereomer) as a white solid: ¹H NMR (CDCl₃) δ 10.9-10.3 (1H, 2 d), 10.08-9.78 (1H, 2 d), 9.25-9.15(1H,m), 8.35-8.10 (1H, 2 m), 7.9-7.85 (1H, 2 s), 7.40-7.05 (10H, m),6.9-6.75 (1H,m), 6.3-5.8 (1H, br s), 5.2-4.65 (2H,m), 4.35-3.5 (3H,m),3.25-3.0 (2H, m), 2.9-2.45 (6H,m), 2.05-1.8 (2H,m), 1.4 (9H,s).

(3S)-(2-{Phenylethyl-[5-(3-phenylpropyl)-1H-imidazole-2-carbonyl]amino}acetylamino)-4-oxobutanoicacid trifluoroacetic acid salt (25) was prepared by the method describedfor 7a to afford 32 mg (82%) as a white solid: ¹ H NMR (CD₃ OD) δ7.05-7.35 (m, 11H), 4.65 (m, 1H), 4.4 (m, 1H), 4.3 (s, 2H), 3.6-4.0 (m,2H), 2.5-2.95 (m, 8H), 2.05 (m, 2H).

7-[5-(3-Phenylpropyl)-1H-imidazole-2-carbonyl]-1,4-dithia-7-azaspiro[4.4]nonane-8(S)-carboxylicacid methyl ester (26). 4-(3-Phenylpropyl)imidazole-2-carboxylic acid(13d) was coupled to 1,4-dithia-7-azaspiro[4.4]nonane-8(S)-carboxylicacid methyl ester hydrobromide (Smith et. al., J. Med. Chem., 31, pp.875-85 (1988)) by the method described for 23 to afford 140 mg (65%) asa yellow gum: ¹ H NMR (CDCl₃) δ 7.34-7.15 (5H, m), 6.98-6.8 (1H, 3 s),5.7-5.65 (0.5 H, m), 5.2-5.1 (1H,m), 4.82-4.75 (0.5H, m), 4.4-4.35 (1H,m), 4.05 (1H,d), 3.75-3.7 (3H, 2 s), 3.4-3.3 (4H,m), 2.95-2.45 (8H, m),2.05-1.95 (2H,m).

(3S)-{7-[5-(3-Phenylpropyl)-1H-imidazole-2-carbonyl]-1,4-dithia-7-azaspiro[4.4]nonane-8(S)-carbonyl}-amino)-4-oxobutanoicacid tert-butyl ester semicarbazone (27). Following the proceduredescribed for 4, the ester 26 was converted to its acid which wassubsequently coupled to (3S)-3-amino-4-oxobutanoic acid tert-butyl estersemicarbazone as described for 24 to give 70 mg (33%) as a brown solid:¹ H NMR (CD₃ OD) δ 7.28-7.10 (5H,m), 6.90 (1H, br s), 4.94 (1H, m),3.96-3.86 (2H,q), 3.35-3.25 (4H,d), 3.0 (2H, s), 2.73-2.59 (6H, m),2.0-1.92 (2H, m),1.44 (9H,s).

(3S)-({7-[5-(3-Phenylpropyl)-1H-imidazole-2-carbonyl]-1,4-dithia-7-azaspiro[4.4]nonane-8(S)-carbonyl}-amino)-4-oxobutanoicacid (28) was prepared by the method described for 7a to afford 17 mg(26%) as a light brown solid: ¹ H NMR (CD₃ OD) δ 7.4 (s, 1H), 7.1-7.25(m, 5H), 4.9 (m, 1H), 4.6 (m, 1H), 4.3 (m, 1H), 3.95 (s, 2H), 3.25-3.4(m, 4H), 3.0 (d, 2H), 2.6-2.8 (m, 5H), 2.45 (m, 1H), 2.05 (m, 2H).##STR126##

4,5-Dihydroimidazole-4-carboxylic esters (29) were prepared by amodification of the procedure described by Jones et al., TetrahedronLett., 29, pp. 3853-56 (1988).

(4R,S) Methyl 2-(2-phenylethyl)-4,5-dihydroimidazole-4-carboxylate(29a). Dry hydrogen chloride was bubbled into a solution ofhydrocinnamonitrile (3.28 ml, 25 mmol) in methanol (125 ml) at 0° C. for45 mins. The solvents were removed to give the imidate salt which wasdissolved in methanol (125 ml) along with methyl-2,3-diaminopropionate(25 mmol) (Jones et al., supra). The mixture was kept at roomtemperature for 2.5 h, then concentrated to a yellow oil. The crudeproduct was purified by column chromatography (10-20%methanol/dichloromethane) to afford 3.52 g (61%) of a colorless glass: ¹H NMR(CDCl₃) δ 7.30-7.15 (5H, m), 4.63 (1H, t, J=9.7), 3.96 (2H, d,J=9.7), 3.72 (3H, s), 3.10 (4H, m), ¹³ C NMR(CDCl₃) δ 171.3, 168.8,138.3, 128.4, 128.2, 126.6, 57.3, 53.0, 47.7, 31.7, 27.9.

(4R, S) Methyl2-[2-(4-trifluoromethylphenyl)ethyl]-4,5-dihydroimidazole-4-carboxylate(29b), was prepared by the method described for 29a to yield 6.80 g(78%) of a colorless solid: mp. 136-141° C.; ¹ H NMR(CDCl₃) δ 7.45 (4H,s), 4.71 (1H, dd, J=8.6,10.8), 4.02 (2H, m), 3.73 (3H, s), 3.19 (4H, m).

Imidazole-4-carboxylic esters 30 were prepared by a modification of theprocedure described by Martin et al., J. Org. Chem., 33, pp. 3758-61(1968).

Methyl 2-(2-phenylethyl)imidazole-4-carboxylate (30a). A mixture of(4R,S) methyl 2-(2-phenylethyl)-4,5-dihydroimidazole-4-carboxylate (29a)(3.40 g, 14.64 mmol), chloroform (75 ml) and manganese (IV) oxide (13.0g, 150 mmol) was heated under reflux for 21 h then filtered hot. Thesolids were washed with chloroform and methanol. The combined filtrateswere concentrated to leave a yellow-brown solid, which was purified bycolumn chromatography (2-5% methanol/dichloromethane) to afford 1.46 g(43%) of a pale yellow solid: mp. 151-155° C.; IR (KBr) 3028, 2946,1720, 1533, 1433, 1348, 1195, 1166; ¹ H NMR(CDCl₃) δ 7.62 (1H, s),7.26-7.02 (5H, m), 3.82 (3H, s), 3.03 (4H, brs), ¹³ C NMR(CDCl₃) δ162.9, 150.2, 140.3, 128.5, 128.2, 126.3, 51.5, 34.5, 30.4. Anal. Calcdfor C₁₃ H₁₄ N₂ O₂ : C, 67.81; H, 6.13; N, 12.16. Found: C, 67.70; H,6.15; N, 12.16.

Methyl 2-[2-(4-trifluoromethylphenyl)ethyl]imidazole-4-carboxylate(30b), was prepared by the method described for 30a. It wasrecrystallised from ethyl acetate to afford 1.88 g (33%) of creamcrystals: mp. 225-26° C.; IR (KBr) 3239, 2951, 1715, 1532, 1331, 1158,1105, 1068; ¹ H NMR (CDCl₃) δ 7.61 (1H, s), 7.54 (2H, d, J=8.1), 7.26(2H, d, J=8.1), 3.89 (3H, s), 3.10 (4H, m). Anal. Calcd for C₁₄ H₁₃ F₃N₂ O₂ : C, 56.38; H, 4.39; N, 9.39; F, 19.11. Found: C, 56.23; H, 4.44;N, 9.33; F, 19.08.

2-(2-Phenylethyl)imidazole-4-carboxylic acid (31a). A mixture of methyl2-(2-phenylethyl)imidazole-4-carboxylate (30a) (1.38 g, 5 mmol),methanol (30 ml) and 1M aqueous sodium hydroxide (30 ml) was heatedunder reflux for 16 h. The methanol was removed under reduced pressure,and the resulting aqueous solution was neutralized with 4M hydrochloricacid, whereupon a pale yellow solid precipitated. The precipitate wascollected, washed with water, and dried to afford 1.18 g (91%) of a paleyellow solid: mp. 117-120° C.; IR (KBr) 3375, 3131, 2616, 2472, 1638,1592, 1551, 1421, 1388, 1360; ¹ H NMR(d₆ -DMSO) δ 7.59 (1H, s), 7.26(5H, m), 2.99 (4H, m). Anal. Calcd for C₁₂ H₁₂ N₂ O₂ 0.25H₂ O: C, 65.29;H, 5.71; N, 12.69. Found: C, 65.00; H, 5.64; N, 12.58.

2-[2-(4-Trifluoromethylphenyl)ethyl]imidazole-4-carboxylic acid (31b),was prepared by the method described for 31a to afford 1.09 g (76%) of apale yellow solid: mp. 126-130° C.; IR (KBr) 3339, 2640-2467, 1638,1589, 1545, 1383, 1323; ¹ H NMR(d₆ -DMSO) δ 7.69 (2H, d, J=8.0), 7.59(1H, s), 7.47 (2H, d, J=8.0), 3.06 (4H, m).

(2R,S, 3S) N²-[2-(2-Phenylethyl)imidazole-4-carbonyl]-N-(tetrahydro-2-benzyl-oxy-5-oxo-3-furanyl)-L-alaninamide(32a). To a solution of (2R,S, 3S) N²-tert-butoxycarbonyl-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-alaninamide(14) (1.59 g, 4.20 mmol; Chapman, Biorg. Med. Chem. Lett., 2, pp. 613-18(1992)) in dichloromethane (15 ml), cooled to 0° C., was addedtrifluoroacetic acid (15 ml). The mixture was stirred at 0° C. for 1 hand then concentrated. The residue was treated with ether and then theether was removed under vacuum. This procedure was repeated twice toyield a pale yellow glass. The solid was dissolved in DMF (20 ml), thendiisopropylethylamine (2.19 ml, 12.6 mmol),2-(2-phenylethyl)imidazole-4-carboxylic acid (31a) (1.0 g, 4.62 mmol),1-(3-dimethylaminopropyl)-3-ethyl carbodiimide hydrochloride (0.89 g,4.62 mmol) and hydroxybenzotriazole (1.14 g, 8.40 mmol) were added tothe solution. The reaction mixture was stirred at room temperature for20 h then poured into brine. The mixture was extracted with ethylacetate (3×50 ml). The combined organic extracts were washed withsaturated aqueous sodium bicarbonate (3×100 ml) then brine (3×100 ml),dried (MgSO₄) and concentrated. The residue was purified by columnchromatography (2-10% isopropanol in dichloromethane then 0-6%isopropanol in ethyl acetate) to yield 1.10 g (55%) of 32a as a mixtureof diastereomers: IR (KBr) 3278, 3065, 1790, 1641, 1577, 1545, 1499,1454, 1120; ¹ H NMR(CDCl₃) δ 10.26 (1H, s), 8.14 (1H, s), 7.66 (d,J=7.0), 7.56 (d, J=7.0), 7.43 (1H, s), 7.31-7.11 (10H, m), 5.49 (d,J=5.6), 5.48 (s), 4.83-4.41 (4H, m), 3.04-2.41 (2H, m), 2.99 (4H, s),1.45 (d, J=7.0), 1.44 (d, J=7.0).

(2R,S, 3S) N² -{2-[2-(4-Trifluoromethylphenyl)ethyl]imidazole-4-carbonyl}-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-alaninamide(32b), was prepared by the method described for 32a to afford 1.08 g(62%) of a pale yellow glass: IR (KBr) 3376, 3284, 3070, 2938, 1791,1642, 1578, 1546, 1327, 1165, 1122, 1068; ¹ H NMR(CDCl₃) δ 7.95 (0.5H,m), 7.55-7.25 (11.5 H, m), 5.53 (s), 5.49 (d, J=5.3), 4.88-4.48 (4H, m),3.11-2.96 (4H, m), 2.91 (1H, m), 2.51 (1H, m), 1.47 (3H, d, J=7.1).

(2R,S, 3S) N²-(2-Benzylimidazole-4-carbonyl)-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-alaninamide(32c), was prepared by the method described for 32a from2-benzylimidazole-4-carboxylic acid (Ger. Offen. DE 3427136) to afford1.13 g (83%) of a yellow glass: IR (CH₂ Cl₂) 3433, 3062, 2990, 1803,1693, 1584, 1504, 1429, 1285, 1258; ¹ H NMR(CDCl₃) δ 9.50 (s), 9.37 (s),7.86 (0.5H, d, J=6.1), 7.56-7.21 (10.5H, m), 7.48 (1H, s), 5.51 (d,J=5.2), 5.48 (s), 4.87-4.41 (4H, m), 4.08 (s), 4.07 (s), 3.03-2.39 (2H,m), 1.46 (3H, d, J=7.0).

(3S)3-{N-[2-(2-Phenylethyl)imidazole-4-carbonyl]-L-alaninyl}amino-4-oxobutanoicacid (33a; A). A mixture of (2R,S, 3S) N²-[2-(2-phenylethyl)imidazole-4-carbonyl]-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-alaninamide(32a) (1.0 g, 2.10 mmol) and 10% palladium on activated carbon (1.0 g)in methanol (50 ml) was stirred under a hydrogen atmosphere for 4.5 h.The resulting mixture was filtered and concentrated to yield a colorlessglass. Recrystallization from methanol-diethyl ether afforded 510 mg(63%) of a colorless solid: mp. 127° C.; IR (KBr) 3360, 3279, 2981,1781, 1732, 1646, 1577, 1547; ¹ H NMR (CD₃ OD) δ 7.54 (1H, s), 7.29-7.12(5H, m), 4.60-4.47 (2H, m), 4.28 (1H, m), 3.01 (4H, s), 2.76-2.39 (2H,m), 1.43 (3H, 2×d, J=7.0, J=7.0), ¹³ C NMR (CD₃ OD) δ 176.2, 176.0,174.7, 174.6, 164.4, 164.3, 150.5, 141.9, 134.8, 129.5, 129.3, 127.3,122.3, 98.8, 98.4, 52.3, 52.0, 50.3, 35.6, 31.2, 18.8, 18.7. Anal. Calcdfor C₁₉ H₂₂ N₄ O₅ H₂ O: C, 56.43; H, 5.98; N, 13.85. Found: C, 56.78; H,5.70; N, 13.77.

(3S) 3-{N-[2-(2-[4-Trifluoromethylphenyl]ethyl)imidazole-4-carbonyl]-L-alaninyl}-amino-4-oxobutanoic acid (33b; C), wasprepared by the method described for 33a to afford 612 mg (73%) of acolorless solid: mp. 120-124° C.; [α]_(D) ²³ +14.3° (c 0.5, MeOH); IR(KBr) 3287, 2985, 2937, 1782, 1732, 1646, 1579, 1547, 1327; ¹ H NMR (CD₃OD) δ 7.56 (2H, d, J=8.0), 7.54 (1H, 9), 7.36 (2H, d, J=8.0), 4.60-4.48(2H, m), 4.28 (1H, m), 3.08 (4H, m), 2.75-2.41 (2H, m), 1.43 (3H, d,J=7.0). Anal. Calcd for C₂₀ H₂₁ F₃ N₄ O₅.0.5H₂ O: C, 51.84; H, 4.78; N,12.09; F, 12.30. Found: C, 51.83; H, 4.72; N, 12.14; F, 12.36.

(3S) 3-[N-(2-Benzylimidazole-4-carbonyl)-L-alaninyl]amino-4-oxobutanoicacid (33c; B), was prepared by the method described for 33a to afford426 mg (64%) of a colorless solid: [α]_(D) ²³ +13.4° (c 0.407, MeOH). IR(KBr) 3260, 3150, 2980, 1779, 1727, 1649, 1573, 1547; ¹ H NMR (CD₃ OD) δ7.58 (1H, s), 7.34-7.22 (5H, m), 4.59-4.47 (2H, m), 4.28 (1H, m), 4.07(2H, s), 2.74-2.41 (2H, m), 1.42 (3H, d, J=6.7); ¹³ C NMR (CD₃ OD) δ175.6, 175.5, 175.0, 164.6, 164.5, 150.1, 138.7, 135.3, 130.0, 129.9,128.2, 122.9, 98.9, 98.5, 52.5, 52.2, 35.5, 35.1, 35.0, 19.0, 18.9.Anal. Calcd for C₁₈ H₂₀ N₄ O₅ H₂ O: C, 55.37; H, 5.68; N, 14.35. FoundC, 55.83; H, 5.75; N, 13.96. MS(FAB, m/z): 373 ((M⁺), 228, 185, 91.##STR127##

5-Benzylpyrrole-2-carboxylic acid (34b). A mixture of Ethyl5-benzylpyrrole-2-carboxylate (0.7 g, 3.05 mmol; Elder et al., SyntheticCommunications, 19, 763-767 (1989)), ethanol (20 ml) and 1M sodiumhydroxide (9.2 ml, 9.2 mmol) was stirred and heated under reflux for 3h. The major part of the ethanol was removed and the remaining liquidwas diluted with water, washed with ether, cooled in ice and acidifiedwith concentrated hydrochloric acid. The mixture was extracted withether. The combined extracts were washed with brine, dried (Na₂ SO₄) andconcentrated to afford 0.567 g (92%) of an off white solid: mp. 130-134°C.; ¹ H NMR(CDCl₃) δ 8.87 (1H, brs), 7.37-6.95 (5H, m), 6.97 (1H, m),6.07 (1H, m), 4.00 (2H, s).

(2R,S, 3S) N²-(Pyrrole-2-carbonyl)-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-alaninamide(35a). A solution of (2R,S, 3S) N²-tert-butoxycarbonyl-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-alaninamide(14) (756 mg, 2.0 mmol) in dry dichloromethane (8 ml) at 0° C. wastreated with trifluoroacetic acid (8 ml) for 1 h and then evaporated todryness. Dry ether was added to the residue and the mixture concentratedto give a viscous oil. The oil was dissolved in dry DMF (10 ml).Pyrrole-2-carboxylic acid (34a) (244 mg, 2.2 mmol) was added and thesolution was cooled in an ice bath before the addition ofN,N-diisopropylamine (0.78 g, 6.0 mmol), 1-hydroxybenzotriazole (0.54 g,4.0 mmol) and ethyl dimethylaminopropyl carbodiimide hydrochloride (0.42g, 2.2 mmol). The resulting mixture was stirred at 25° C. for 17 h andthen saturated aqueous sodium chloride (30 ml) was added. The mixturewas extracted with ethyl acetate (3×20 ml) and the combined organicextracts were washed with 5% aqueous sodium bicarbonate (3×10 ml) andbrine (10 ml), dried (MgSO₄) and concentrated. Flash chromatography (25%hexane-ethyl acetate) afforded 557 mg (75%) of a 1:1 mixture ofdiastereomers as a white glassy solid: mp. 85-90° C.; IR (KBr) 3288,1789, 1665, 1629, 1557 and 1122; ¹ H NMR(d₆ -DMSO) δ 11.46 (1H, bs),8.55 (0.5H, d, J=7.0), 8.30 (0.5H, d, J=7.6), 8.06 (0.5H, d, J=7.0),8.04 (0.5H, d, J=7.6), 7.36-7.30 (5H, m), 6.88-6.85 (2H, m), 6.10-6.07(1H, m), 5.63 (0.5H, d, J=5.0), 5.42 (0.5H, s), 4.72 (2H, q, J=12.2),4.74-4.25 (2H, m), 3.14-2.35 (2H, m), 1.29, 1.25 (3H, 2×d, J=7.2).

(2R,S, 3S) N²-(5-Benzylpyrrole-2-carbonyl)-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-alaninamide(35b), was prepared from 5-benzylpyrrole-2-carboxylic acid (34b) by themethod described for compound 35a (65%). Data is given for a singlediastereomer. ¹ H NMR (d₆ -DMSO) δ 11.37 (1H, brs,), 8.27 (1H, d,J=7.4), 7.93 (1H, d, J=7.6), 7.33-7.16 (10H, m), 6.76 (1H, m), 5.82 (1H,m), 5.62 (1H, d, J=5.2), 4.76 (1H, d, J=12.0), 4.65 (1H, m), 4.62 (1H,d, J=12.2), 4.47 (1H, m), 3.88 (2H, s), 2.77 (1H, dd, J=9.0,18.0), 2.5(dd), 1.23 (3H, d, J=7.0).

(3S) 3-[N-(Pyrrole-2-carbonyl)-L-alaninyl]amino-4-oxobutanoic acid (36a;D). A mixture of (35a) (612 mg; 1.65 mmol), methanol (40 ml) and 10%palladium on carbon (500 mg) was vigorously stirred under an atmosphereof hydrogen for 4 h. The mixture was filtered through a 0.2 μM nylonmembrane then concentrated. The residue was purified by flashchromatography (5-10% methanol in methylene chloride) to afford thehemihydrate of (36a) (223 mg, 48%) as a white solid after precipitationfrom an ethyl acetate-ether mixture. There were traces of solvent in theproduct: mp. 96-100° C.; IR (KBr) 3381, 1774, 1729 (EtOAc), 1632, 1558,1523, 1123; ¹ H NMR(CD₃ OD) δ 6.94-6.85 (2H, m), 6.17 (1H, dd, J=3.8 and2.6), 4.58 (0.5H, d, J=3.94), 4.56 (0.5H, d, J=4.24), 4.51 (1H, q,J=7.16), 4.35-4.20 (1H, m), 2.74-2.40 (2H, m), 1.42 and 1.41 (3H, 2×d,J=7.13).

(3S) 3-[N-(5-Benzylpyrrole-2-carbonyl)-L-alaninyl]amino-4-oxobutanoicacid (36b), was prepared (41%) from 35b by the method described forcompound 36a, to afford an off white solid: mp. 109-112° C.; [α]_(D) ²⁵+6.3° (c 0.3, methanol); IR (KBr) 3368, 1724, 1630, 1530, 1453, 1414,1233, 1049; ¹ H NMR(d₄ methanol) δ 7.25-7.11 (5H, m), 6.76 (1H, d,J=3.5), 5.84 (1H, d, J=3.5), 4.51 (1H, m), 4.43 (1H, q, J=7.1), 4.23(1H, m), 2.5 (2H, m),1.35 (3H, d, J=7.0). Anal. Calcd for C₁₉ H₂₁ N₃O₅.1.75 H₂ O: C, 56.64; H, 6.13; N, 10.43. Found: C, 56.34; H, 5.72; N,10.00. ##STR128## (2R,S, 3S) 1-(Indole-2-carbonyl)-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-prolinamide(38). Trifluoroacetic acid (4 ml) was added to a solution of (2R,S, 3S)1-tert-butoxycarbonyl-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-prolinamide(15) (0.607 g, 1.5 mmol) in dichloromethane (4 ml) at 0° C. The mixturewas stirred at 0° C. for 75 min. The mixture was concentrated, and theresidue treated with diethyl ether, then the ether was removed undervacuum. This procedure was repeated twice to yield a yellow oil, whichwas dissolved in DMF (12 ml). Diisopropyl-ethylamine (0.78 ml, 4.5 mmol)followed by indole-2-carboxylic acid (266 mg, 1.65 mmol),1-(3-dimethylaminopropyl)-3-ethyl carbodiimide hydrochloride (316 mg,1.65 mmol) and hydroxybenzotriazole (405 mg, 3 mmol) were then added tothe solution. The mixture was stirred at room temperature for 20 h thenpoured into brine. The mixture was extracted with ethyl acetate (3×30ml). The combined organic extracts were washed with saturated aqueoussodium bicarbonate (2×60 ml) then brine (2×60 ml), dried (MgSO₄),filtered and concentrated. The residue was purified by columnchromatography (ethyl acetate) to afford 518 mg (77%) of a mixture ofdiastereomers: IR (KBr) 3314, 1780, 1677, 1609, 1524, 1435, 1406, 1344;¹ H NMR (d₆ -DMSO), δ 11.58 (1H, m), 8.81-8.41 (1H, m), 7.71-6.67 (10H,m), 5.70 (d, J=5.2), 5.48 (s), 4.89-4.29 (4H, m), 3.99-3.74 (2H, m),3.20-2.44 (2H, m), 2.39-1.77 (4H, m).

(3S) 3-[1-(Indole-2-carbonyl)-L-prolinyl]amino-4-oxobutanoic acid (39).A mixture of (2R,S, 3S)1-(indole-2-carbonyl)-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)-L-prolinamide(38) (478 mg, 1.07 mmol) and 10% palladium on carbon (475 mg) andmethanol (150 ml) was stirred under a hydrogen atmosphere for 6 h. Theresulting mixture was filtered and concentrated to yield a colorlessglass. Recrystallization from a mixture of methanol and diethyl etherafforded 202 mg (53%) of a colorless solid: mp. 135-138° C.; [α]_(D) ²⁴-44° (c 0.25, CH₃ OH); IR (KBr) 3287, 2977, 2879, 1781, 1725, 1716,1667, 1662, 1600, 1529, 1441, 1346; ¹ H NMR(CD₃ OD) δ 7.65 (1H, d,J=8.0), 7.44 (1H, d, J=8.4), 7.22 (1H, m), 7.09-6.84 (2H, m), 4.62 (2H,m), 4.29 (1H, m), 4.15-3.73 (2H, m), 2.74-1.72 (6H, m). ##STR129##

Methyl 2-(3,5-dihydro-7-methyl-4-oxo-4H-pyrrolo [3,2-d]pyrimidin-3-yl)acetate (40). Freshly prepared methyl glycinate (1.25 g,14 mmol) was added to a stirred solution of ethyl 3-[N-(dimethylamino)methylene]amino-4-methylpyrrole-2-carboxylate (1.56 g, 7.0 mmol; Lim etal., J. Org. Chem., 44, pp. 3826-29 (1979)) in dry methanol (60 ml). Theresulting mixture was kept at 70° C. Two further batches of methylglycinate (1.25, 14.0 mmol) were added after 18 h and 42 h heating. Themixture was cooled and filtered 24 h after the final addition. Thefiltrate was concentrated and the residue purified by flashchromatography (2-5% methanol/chloroform) to afford 0.54 g (35%) of awhite crystalline solid: mp. 233-235° C. (recrystallized from ethylacetate); IR (KBr) 3135, 2958, 1745, 1675, 1254; ¹ H NMR (d₆ -DMSO) δ11.90 (1H, s), 8.07 (1H, s), 7.23 (1H, s), 4.83 (2H, s), 3.69 (3H, s),2.16 (3H, s). Anal. Calcd for C₁₀ H₁₁ N₃ O₃ 0.1H₂ O: C, 53.85; H, 5.07;N. 18.84. Found: C, 53.85; H, 4.96; N, 18.81; MS(70 eVE.I.) m/e 222, 221(M⁺, 100%), 189, 162, 133, 105.

2-(3,5-Dihydro-7-methyl-4-oxo-4H-pyrrolo[3,2-d]pyrimidin-3-yl)aceticacid, sodium salt (41). A suspension of 40 (354 mg, 1.6 mmol) inmethanol (15 ml) was treated with 0.5N sodium hydroxide (4.8 ml) and theresulting mixture was stirred at 25° C. for 1 h. The reaction mixturewas filtered to afford the hemihydrate of 41 (354 mg, 97%) as a whitecrystalline solid: mp. >340° C. (recrystallized from methanol); IR (KBr)3461, 3143, 1676, 1666, 1605, 1415; ¹ H NMR(d₆ DMSO) δ 11.63 (1H, s.),7.83 (1H, s), 7.11 (1H, d, J=2.0), 4.24 (2H, s), 2.14 (3H, s). Anal.Calcd for C₉ H₈ N₃ O₃ Na. 0.5H₂ O: C, 45.39; H, 3.81; N, 17.64. Found:C, 45.57; H, 4.05; N, 17.39.

(2R,S, 3S)2-(3,5-Dihydro-7-methyl-4-oxo-4H-pyrrolo[3,2-d]pyrimidin-3-yl)-N-(tetrahydro-2-benzyloxy-5-oxo-3-furanyl)acetamide(42). A suspension of the sodium salt 41 (344 mg, 1.5 mmol) in dry DMF(15 ml) was treated with ethyl dimethylaminopropyl carbodiimidehydrochloride (373 mg, 1.95 mmol) and 1-hydroxybenzo-triazole (405 mg,3.0 mmol). The mixture was kept at 25° C. for 1 h then (2R,S, 3S)N-allyloxycarbonyl-3-amino-2-benzyloxy-5-oxotetrahydrofuran (437 mg, 1.5mmol; Chapman, Biorg. Med. Chem. Lett., 2, pp. 613-18 (1992)) and (Ph₃P)₂ PdCl₂ (25 mg) were added followed by the dropwise addition ofn-tributyltin hydride (0.6 ml, 2.25 mmol). The resulting mixture wasstirred at 25° C. for 1 h then water (20 ml) was added. The mixture wasextracted with ethyl acetate (3×15 ml), and the combined organicextracts were washed with water (5 ml), dried (MgSO₄), and concentratedto afford a mixture of diastereomers. Evaporation of the aqueous phaseand purification of the residue by flash chromatography (5%methanol/chloroform) gave an additional quantity affording a total 182mg of 42 (31%): m.p. 240-244° C.; IR (KBr) 3274, 1772, 1691, 1664, 1562;¹ H NMR (d₆ -DMSO) δ 11.81 (1H, s), 8.85 (0.6H, d, J=6.6), 8.72 (0.4H,d, J=7.4), 7.98 (0.6H, s), 7.95 (0.4H, s), 7.40-7.30 (5H, m), 7.20 (1H,d, J=2.2), 5.61 (0.4H, d, J=5.0), 5.46 (s), 4.85-4.60 (m), 4.28 (m),3.20-2.35 (2H, m), 2.16 (3H, s).

(3S)-3-[2-(3,5-Dihydro-7-methyl-4-oxo-4H-pyrrolo[3,2-d]pyrimidin-3-yl)-1-oxo-ethylamino]-4-oxobutanoicacid (43). A mixture of 42 (131 mg, 0.33 mmol), in methanol (50 ml) and10% palladium on carbon (100 mg) was stirred vigorously under anatmosphere of hydrogen for 2 h. An additional quantity of catalyst (100mg) was added and the mixture hydrogenated for a further 2 h. Themixture was filtered through a 0.2 μM nylon membrane, and concentrated.The residue was recrystallized from methanol/diethyl ether to afford 79mg (78%) of 43 as a hygroscopic white solid: mp. 222-226° C.; (decomp.);[α]_(D) ³² +0.5 (c 0.02, MeOH); IR (KBr) 3282, 1680, 1558, 1425 1275; ¹H NMR (CD₃ OD) δ 8.03 (1H, s), 7.18 (1H, d, J=0.7), 4.79-4.74 (2H, m),4.63-4.59 (1H, 2×d, J=3.6), 4.36-4.25 (1H, m), 2.78-2.39 (2H, m), 2.24(3H, d, J=0.7). Anal. Calcd for C₁₃ H₁₄ N₄ O₅.1.4H₂ O: C, 47.10; H,5.12; N, 16.90. Found: C, 47.00; H, 4.79; N, 16.59. FABMS m/e 307, 306(M⁺), 244, 207, 190, 152, 115 (100%). ##STR130##

(1S,9S) t-Butyl6,10-dioxo-octahydro-9-(3-phenylpropionylamino)-6H-pyridazino[1,2-a][1,2]diazepine-1-carboxylate (44a). To a solution of (1S,9S)t-butyl9-amino-6,10-dioxo-octahydro-6H-pyridazino[1,2-a][1,2]diazepine-1-carboxylate (690 mg; 2.32 mmol; GB 2128984) indioxane (16 ml) and water (4 ml) at 0° C. was added solid sodiumbicarbonate (292 mg; 3.48 mmol) followed by dropwise addition of3-phenylpropionyl chloride (470 mg; 2.78 mmol). The mixture was stirredat room temperature for 2 h then more sodium bicarbonate (200 mg; 2.38mmol) and 3-phenylpropionyl chloride (100 mg; 0.6 mmol) was added. Themixture was stirred for a further 2 h at room temperature, diluted withethyl acetate (50 ml), washed with saturated sodium bicarbonate (2×25ml) then dried (MgSO₄) and concentrated. The residue was purified byflash chromatography (0-50% ethyl acetate/chloroform) and finallycrystallized by trituration with ether to afford 860 mg (86%) of a whitesolid: mp. 137-138° C.; [α]_(D) ²³ -95.1° (c 0.549, CH₂ Cl₂); IR (KBr)3327, 1736, 1677, 1664, 1536, 1422, 1156; ¹ H NMR (CDCl₃) δ 7.24 (5H,m), 6.50 (1H, d, J=7.5), 5.24 (1H, m), 4.90 (1H, m), 4.60 (1H, m), 3.44(1H, m), 2.93 (2H, m), 2.84 (1H, m), 2.64 (1H, m), 2.54 (2H, m), 2.26(2H, m), 1.70 (4H, m), 1.70 (9H, s). MS(FAB, m/z): 430 (M⁺ +1), 374,242, 105, 91.

(1S,9S)t-Butyloctahydro-10-oxo-9-(3-phenylpropionylamino)-6H-pyridazino-[1,2-a][1,2]diazepine-1-carboxylate (44b), was prepared from (1S, 9S)-t-butyl9-amino-octahydro-10-oxo-6H-pyridazino[1,2-a][1,2]diazepine-1-carboxylate(Attwood et al., J. Chem. Soc. Perkin 1, pp. 1011-19 (1986)) as for 44a,to afford 810 mg (81%) of a colorless oil: [α]_(D) ²³ -33.5° (c 0.545,CH₂ Cl₂); IR (film) 3334, 2935, 1737, 1728, 1659, 1642; ¹ H NMR (CDCl₃)δ 7.24 (5H, m), 6.75 (1H, d, J=6.7), 5.27 (1H, m), 4.92 (1H, m), 3.39(1H, m), 3.03 (4H, m), 2.55 (3H, m), 2.33 (1H, m), 2.17 (1H, m), 1.80(5H, m), 1.47 (9H, s), 1.39 (1H, m). MS(FAB, m/z): 416 (M⁺ +1), 360,211, 143, 97.

(1S,9S)6,10-Dioxo-octahydro-9-(3-phenylpropionylamino)-6H-pyridazino[1,2-a][1,2]diazepine-1-carboxylic acid (45a). To a solution of (1S,9S) t-butyl6,10-dioxo-octahydro-9-(3-phenylpropionylamino)-6H-pyridazino[1,2-a][1,2]diazepine-1-carboxylate (44a) (800 mg; 1.863 mmol) in drydichloromethane (5 ml) at 0° C. was added trifluoroacetic acid (5 ml).The solution was stirred at room temperature for 3 h then concentrated.Dry ether (10 ml) was added to the residue then removed under vacuum.This process was repeated three times to afford a crystalline solid. Thesolid was triturated with ether and filtered to afford 590 mg (85%) of awhite crystalline solid: mp. 196-197.5° C.; [α]_(D) ²³ -129.5° (c 0.2,CH₃ OH); IR (KBr) 3237, 1729, 1688, 1660, 1633, 1574, 1432, 1285, 1205;¹ H NMR (CD₃ OD) δ 8.28 (1H, d, J=7.4), 7.22 (5H, m), 5.32 (1H, dd,J=5.9, 2.9), 4.75 (1H, m), 4.51 (1H, m), 3.50 (1H, m), 3.01 (1H, m),2.91 (2H, m), 2.55 (2H, m), 2.29 (3H, m), 1.95 (2H, m), 1.71 (2H, m) .Anal. Calcd for C₁₉ H₂₃ N₃ O₅ : C, 61.12; H, 6.21; N, 11.25. Found: C,60.80; H, 6.28; N, 10.97. MS(FAB, m/z) 374 (M⁺ +1), 242, 105, 91.

(1S, 9S)Octahydro-10-oxo-9-(3-phenylpropionylamino)-6H-pyridazino[1,2-a]-[1,2]diazepine-1-carboxylicacid (45b), was prepared from (1S, 9S) t-butyloctahydro-10-oxo-9-(3-phenylpropionylamino)-6H-pyridazino[1,2-a][1,2]diazepine-1-carboxylate (44b) by the method described for compound45a to afford 657 mg (96%) of 45b as a crystalline solid: mp. 198-202°C.; [α]_(D) ²³ -86.2° (c 0.5, CH₃ OH); IR (KBr) 3294, 2939, 1729, 1645,1620, 1574, 1453, 1214; ¹ H NMR (CD₃ OD) δ 7.92 (1H, d, J=7.9), 7.20(5H, m), 5.29 (1H, m), 4.90 (1H, m), 3.47 (1H, m), 3.08 (2H, m), 2.90(2H, m), 2.55 (3H, m), 2.36 (1H, m), 1.81 (5H, m), 1.43 (2H, m). MS(FAB,m/z) 360 (M⁺ +1), 211,143,91.

[3S, 2R,S,(1S,9S)]N-(2-Benzyloxy-5-oxotetrahydrofuran-3-yl)-6,10-dioxo-octahydro-9-(3-phenylpropionylamino)-6H-pyridazino[1,2-a][1,2]diazepine-1-carboxamide(46a). To a solution of (1S, 9S)6,10-dioxo-octahydro-9-(3-phenyl-propionylamino)-6H-pyridazino[1,2-a][1,2]diazepine-1-carboxylic acid (45a) (662 mg; 1.773 mmol) in drydichloromethane (9 ml) and dry dimethyl formamide (3 ml) at roomtemperature was added bis(triphenylphosphine)palladium chloride (30 mg)and (3S, 2R,S)-3-allyloxycarbonylamino-2-benzyloxy-5-oxotetrahydrofuran(Chapman, Biorg. Med. Chem. Lett., 2, pp. 613-18 (1992)) (568 mg; 1.95mmol) followed by dropwise addition of tri-n-butyltin hydride (1.19 g;4.09 mmol). 1-Hydroxy-benzotriazole (479 mg; 3.546 mmol) was added tothe mixture and the mixture was cooled to 0° C. before addition of1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (408 mg;2.128 mmol). The mixture was stirred at room temperature for 3.25 h thendiluted with ethyl acetate (50 ml), washed twice with dilutehydrochloric acid (20 ml), twice with saturated sodium bicarbonate (20ml), once with brine then dried (MgSO₄) and concentrated. The resultingoil was purified by flash chromatography (0-100% ethylacetate/chloroform) to afford 810 mg (81%) of 46a as a mixture ofanomers: mp. 92-94° C.; IR (KBr) 3311, 1791, 1659, 1651, 1536; ¹ HNMR(CDCl₃) δ 7.49, 6.56 (1H, 2d, J=6.7, 7.8), 7.29 (10H, m), 6.37, 6.18(1H, 2d, J=7.7,7.6), 5.56, 5.34 (1H, d, s, J=5.2), 5.08-4.47 (6H),3.18-2.80 (5H), 2.62-2.28 (5H), 2.04-1.53 (5H). MS(FAB, m/z), 563 (M⁺+1), 328, 149, 91.

[3S, 2R,S, (1S, 9S)]N-(2-Benzyloxy-5-oxotetrahydrofuran-3-yl)-octahydro-10-oxo-9-(3-phenylpropionylamino)-6H-pyridazino[1,2-a][1,2]diazepine-1-carboxamide (46b), was prepared from 45b by the methoddescribed for 46a to yield 790 mg (96%) of a glass: m.p. 58-60° C.; IR(KBr) 3316, 2940, 1793, 1678, 1641, 1523, 1453, 1120; ¹ H NMR (CDCl₃) δ7.28 (10H, m), 6.52, 6.42 (1H, 2d, J=7.2, 7.1), 5.53, 5.44 (1H, d, s,J=5.2), 5.35 (1H, m), 4.6-4.9, 4.34 (4H, m), 3.1-2.8 (6H, m), 2.6-2.1(7H), 1.95-1.05 (5H). MS(FAB, m/z), 549 (M⁺ +1), 400, 310, 279, 91.

[3S, (1S, 9S)]3-(6,10-Dioxo-octahydro-9-(3-phenylpropionylamino)-6H-pyridazino[1,2-a][1,2]diazopine-1-carboxamido)-4-oxobutanoic acid (47a). A mixture of[3S, 2R,S, (1S, 9S)]N-(2-benzyloxy-5-oxotetrahydrofuran-3-yl)-6,10-dioxo-octahydro-9-(3-phenylpropionylamino)-6H-pyridazino[1,2-a][1,2]diazepine-1-carboxamide (46a) (205 mg; 0.364 mmol), 10% palladiumon carbon (200 mg) and methanol (20 ml) was stirred under hydrogen atatmospheric pressure for 5 h. The mixture was filtered then concentratedto yield 154 mg (90%) of a glass: mp. 116-118° C.; [α]_(D) ²³ -140° (c0.1, CH₃ OH) ; IR (KBr) 3323 (br), 1783, 1731, 1658, 1539, 1455, 1425; ¹H NMR (CD₃ OD) δ 7.21 (5H, m), 5.17 (1H, m), 4.73 (1H, m), 4.50 (2H, m),4.23 (1H, m), 3.38 (1H, m), 3.06 (1H, m), 2.91 (2H, m), 2.73-2.18 (6H,m) and 2.01-1.59 (5H, m). Anal. Calcd for C₂₃ H₂₇ N₄ O₇ +H₂ O: C, 56.32;H, 6.16; N, 11.42. Found: C, 56.29; H, 6.11; N, 11.25. MS(FAB, m/z) 473(M⁺ +1), 176, 149, 105, 91.

[3S,(1S,9S)]3-(Octahydro-10-oxo-9-(3-phenylpropionylamino)-6H-pyridazino-[1,2-a][1,2]diazepine-1-carboxamido)-4-oxobutanoic acid (47b), was preparedfrom 46b by the method described for 47a. The residue was purified byflash chromatography (0-10% methanol/chloroform) to afford 65 mg (52%)of a glass; m.p. 87-90° C.; [α]_(D) ²³ -167.0° (c 0.1, methanol); IR(KBr) 3329, 2936, 1786, 1727, 1637; ¹ H NMR (CD₃ OD) δ 7.23 (5H, m),5.29 (1H, m), 4.83 (1H, m), 4.59 (1H, d, J=3.6), 4.29 (1H, m), 3.3-3.0(3H, m), 2.91 (2H, m), 2.70-2.34 (5H, m), 2.19 (2H, m), 1.75 (4H, m),1.36 (2H, m). Anal. Calcd for C₂₃ H₃₀ N₄ O₆ +0.5H₂ O: C, 59.09; H, 6.68;N, 11.98. Found: C, 58.97H,; 6.68; N, 11.73. MS (FAB, m/z) 459 (M⁺ +1),310, 149, 105, 91.

    ______________________________________                                        1 #STR131##                                                                   2 #STR132##                                                                          R.sub.1   R.sub.2     R.sub.3                                          ______________________________________                                        (a)      PhCH.sub.2  H           (S)Me                                        (b)      PhCH.sub.2  CH.sub.2 Ph H                                            (c)      PhCH.sub.2  (CH.sub.2).sub.2 Ph                                                                       H                                            (d)      PhCH.sub.2  nBu         H                                            (e)      PhCH.sub.2  Me          H                                            (f)      PhCH.sub.2  Ph          H                                            (g)      PhCH.sub.2  H           H                                            (h)      PhCH.sub.2  CH.sub.2 Ph (S)--Me                                      (i)      Ph(CH.sub.2).sub.2                                                                        CH.sub.2 Ph H                                            ______________________________________                                    

Pyridones 48 were prepared by the method described by Damewood et al.,J. Med. Chem., 37, pp. 3303-12 (1994)). Compound 48d is new.

3-Benzyloxycarbonylamino-6-butyl-pyrid-2-one (48d), was isolated as acream solid: mp. 158-160° C.; IR (KBr) 3382, 2953, 2930, 2866, 1729,1643, 1524, 1468, 1202, 1044; ¹ H NMR (d₆ -DMSO) δ 8.26 (1H, s), 7.72(1H, d), 7.39 (5H, m), 6.00 (1H, d), 5.14 (2H, s), 2.41 (2H, t), 1.52(2H, m), 1.24 (2H, m), 0.87 (3H, t). Anal. Calcd for C₁₇ H₂₀ N₂ O₃ : C,67.98; H, 6.71; N, 9.33. Found: C, 67.69; H, 6.68; N, 9.20. MS CI M⁺=300 (m)) 28%.

(2S) Methyl2-[3-benzyxoxycarbonylamino-1,2-dihydro-2-oxo-1-pyridyl]propionate(49a). Sodium hydride (80% oil dispersion) (0.35 g, 11.64 mmole) wasadded to a stirred mixture of 3-(benzyloxycarbonylamino)pyrid-2-one(48a) (2.58 g, 10.58 mmol) and tetrahydrofuran (100 ml) at roomtemperature. The mixture was stirred for 10 mins. The resulting solutionwas added to a solution of 2(R) methyl-2((trifluoromethane)sulphonyloxy)propionate (2.5 g, 10.58 mmole; Feenstra et al.,Tetrahedron Lett., 28, pp. 1215-18 (1987)) in tetrahydrofuran (5 ml) atroom temperature during 10 mins. The mixture was stirred at roomtemperature for 80 mins then poured into ethyl acetate. The mixture waswashed twice with 1M HCl, twice with aqueous sodium bicarbonate thenbrine. It was dried (MgSO₄) and concentrated. The residue was purifiedby flash chromatography (30% ethyl acetate/hexane) to afford 2.945 g(84%) of a colorless solid: mp. 96-7°; [α]_(D) ²⁰ -71.36 (c 2.5, CHCl₂);IR (KBr) 3370, 1764, 1729, 1648, 1602, 1564, 1523, 1515, 1503, 1449,1359, 1203, 1064; ¹ H NMR(CDCl₃) δ 8.04 (1H, d, J=7.2), 7.86 (1H, s),7.36 (5H, m), 6.98 (1H, dd, J=7.1, J=1.7), 6.30 (1H, t, J=7.2), 5.46(1H, q, J=7.4), 5.20 (2H, s), 3.74 (3H, s), 1.66 (3H, d, J=7.4). Anal.Calcd for C₁₇ H₁₈ N₂ O₅ : C, 61.81; H, 5.49; N, 8.48. Found: C, 61.49;H, 5.51; N, 8.41. MS(FAB, m/z) 331 (M⁺ +1), 299, 223, 196, 163, 91.

Methyl[6-benzyl-3-benzyloxycarbonylamino-1,2-dihydro-2-oxo-1-pyridyl]-acetate(49b). Sodium hydride (80% oil dispersion) (0.65 g, 26.2 mmole) wasadded to a stirred mixture of 6-benzyl-3(benzyloxycarbonylamino)pyrid-2-one (48b) (7.3 g, 2.18 mmol) and tetrahydrofuran (150 ml) atroom temperature. The mixture was stirred for 10 mins, treated withmethyl bromoacetate (2.5 ml, 26.2 mmol) and kept for 3 h. The resultingmixture was poured onto a mixture of ice and 1M HCl. The resulting solidwas filtered off then dissolved in dichloromethane. The resultingsolution was dried (MgSO₄), decolourized with charcoal and concentrated.The residue was purified by chromatography (2-5% ethylacetate/dichloromethane) to afford 7.2 g (81%) of colorless crystals:mp. 117-9°; IR (KBr) 3375, 1753, 1730, 1651, 1605, 1513, 1384, 1223,1185, 1071; ¹ H NMR (CDCl₃) δ 8.02 (1H, d, J=7.5), 7.78 (1H, s), 7.31(8H, m), 7.10 (2H, m), 6.15 (1H, d, J=7.5), 5.20 (2H, s), 4.70 (2H, s),3.88 (2H, s), 3.66 (3H, s).

The following compounds were prepared in a similar manner:

Methyl[3-benzyloxycarbonylamino-1,2-dihydro-2-oxo-6-phenylethyl-1-pyridyl]-acetate(49c). 97% yield: m.p. 102-4° C. IR (KBr) 3245, 3232, 1741, 1725, 1648,1600, 1526, 1216; ¹ H NMR (d₆ -DMSO) δ 8.45 (1H, s), 7.76 (1H, d,J=7.6), 7.35 (10H, m), 6.15 (1H, d, J=7.6), 5.15 (2H, s), 4.85 (2H, s),3.68 (3H, s), 2.86 (4H, s).

Methyl[3-benzyloxycarbonylamino-6-butyl-1,2-dihydro-2-oxo-1-pyridyl]-acetate(49d). 90% yield: mp. 111-112° C.; IR (KBr) 3393, 1738, 1731, 1645,1598, 1517, 1225, 1208; ¹ H NMR (d₆ -DMSO) δ 8.39 (1H, s), 7.78 (1H, d,J=7.7), 7.35 (5H, m), 6.17 (1H, d, J=7.7), 5.15 (2H, s), 4.80 (2H, s),3.67 (3H, s), 1.38 (6H, m), 0.89 (3H, t).

Methyl[3-benzyloxycarbonylamino-1,2-dihydro-6-methyl-2-oxo-1-pyridyl]-acetate(49e). 84% yield as a colorless solid: mp. 115-6° C.; IR (KBr) 3246,1740, 1725, 1649, 1598, 1573, 1535, 1417, 1365, 1259, 1219, 1193, 1090,1068, 1006; ¹ H NMR (d₆ -DMSO) δ 8.40 (1H, s), 7.75 (1H, d, J=7.6), 7.38(5H, m), 6.20 (1H, d, J=7.6), 5.15 (2H, s), 4.85 (2H, s), 3.68 (3H, s),2.26 (3H, s).

Methyl [3-benzyloxycarbonylamino-1,2-dihydro-6-phenyl-1-pyridyl]-acetate(49f). 67% yield as a colorless oil: IR (KBr) 3266, 1739, 1727, 1646,1606, 1566, 1517, 1490, 1365, 1213, 1163, 1075; ¹ H NMR (CDCl₃) δ 8.15(1H, d), 7.85 (1H, s), 7.39 (10H, m), 6.22 (1H, d), 5.22 (2H, s), 4.57(2H, s), 3.74 (3H, s).

Methyl [3-benzyloxycarbonylamino-1,2-dihydro-2-oxo-1-pyridyl]-acetate(49 g). 80% yield as a colorless crystalline solid: m.p. 110-111° C. IR(KBr) 3385, 1745, 1726, 1650, 1601, 1512, 1502, 1378, 1369, 1358, 1215,1195, 1162, 1067; ¹ H NMR (CDCl₃) δ 8.06 (1H, d), 7.84 (1H, s), 7.36(5H, m), 6.88 (1H, dd), 6.27 (1H, t), 5.20 (2H, s), 4.68 (2H, s), 3.78(3H, s). Anal. Calcd for C₁₆ H₁₆ N₂ O₅ : C, 60.75; H, 5.10; N, 8.85.Found: C, 60.65; H, 5.15; N, 8.85. MS FAB (+)M+=317 (M+1).

2(S) Methyl2-methyl-[6-benzyl-(3-benzyloxycarbonyl-amino)-1,2-dihydro-2-oxo-1-pyridyl]-acetate(49 h), was prepared by the method used in the preparation of compound49a to afford (58%) an oil; [α]_(D) ²⁵ -25.0° (c 1, CH₂ Cl₂); IR (KBr)3381, 1736, 1650, 1604, 1513, 1218, 1190, 1068; ¹ H NMR (CDCl₃) δ 7.97(1H, d), 7.78 (1H, s), 7.4-7.14 (10H, m), 6.17 (1H, d), 5.19 (2H, s),4.64 (1H, q), 3.98 (2H, s), 3.62 (3H, s), 1.31 (3H, d).

Methyl[6-benzyl-1,2-dihydro-2-oxo-3-(2-phenylethoxy)-carbonylamino-1-pyridyl]acetate(49i), was isolated (88%) as a colorless solid: mp. 130-133° C.; IR(KBr) 3363, 1746, 1732, 1651, 1604, 1515, 1368, 1231, 1212, 1185; ¹ HNMR (CDCl₃) δ 8.00 (1H, d, J=7.0), 7.68 (1H, s), 7.36-7.10 (10H, m),6.15 (1H, d, J=7.6), 4.7 (2H, s), 4.38 (2H, t, J=7.0), 3.88 (2H, s),3.67 (3H, s), 2.98 (2H, t, J=7). ##STR133##

2(S) Methyl 2[3-amino-1,2-dihydro-2-oxo-1-pyridyl]propionate (50a). Amixture of 2(S)methyl-2[3-benzyloxycarbonylamino-1,2-dihydro-2-oxo-1-pyridyl)propionate(49a) (2.75 g, 8.33 mmol), methanol (100 ml), and 10% palladium oncarbon (300 mg) was stirred under an atmosphere of hydrogen for 30 min.The mixture was filtered and concentrated to afford 1.63 g (100%) of acolorless solid: ¹ H NMR (d₆ -DMSO) δ 8.35 (1H, brs), 7.46 (1H, d), 7.22(1H,d), 6.29 (1H, t), 5.22 (1H, q), 3.63 (3H, s), 1.55 (3H, d).

The following compounds were prepared in a similar manner:

Methyl [3-amino-6-benzyl-1,2-dihydro-2-oxo-1-pyridyl]acetate (50b). 100%yield as a grey solid: mp. 134-6° C.; IR (KBr) 3418, 3312, 1723, 1658,1596, 1548, 1435, 1290, 1245, 1011; ¹ H NMR (d₆ -DMSO) δ 7.25 (5H, m),6.45 (1H, d, J=7.4), 5.92 (1H, d, J=7.4), 5.00 (2H, s), 4.63 (2H, s),3.88 (2H, s), 3.51 (3H, s).

Methyl[3-amino-1,2-dihydro-2-oxo-6-phenylethyl-1-pyridyl]acetate (50c).99% yield as a viscous oil: IR (KBr) 3456, 341, 2953, 1745, 1649, 1600,1548, 1219; ¹ H NMR (CDCl₃) δ 7.25 (5H, m), 6.51 (1H, d, J=7.4), 5.92(1H, d, J=7.4), 4.79 (2H, s), 3.77 (3H, s), 2.80 (4H, m).

Methyl[3-amino-6-butyl-1,2-dihydro-2-oxo-1-pyridyl]acetate (50d). 97% asa brown solid: mp. 75-7° C.; IR (KBr) 3437, 3342, 2955, 1745, 1655,1609, 1550, 1432, 1301, 1222, 1200; ¹ H NMR (CDCl₃) δ 6.53 (1H, d,J=6.8), 5.93 (1H, d, J=6.8), 4.81 (2H, s), 3.77 (3H, s), 2.44 (2H, t),1.45 (4H, m), 0.93 (3H, t).

Methyl[3-amino-1,2-dihydro-6-methyl-2-oxo-1-pyridyl]acetate (50e), wasisolated (100%) as a colorless crystalline solid: mp. 87-9° C.; IR (KBr)3442, 3326, 1735, 1647, 1600, 1549, 1434, 1407, 1383, 1366, 1225, 1209;¹ H NMR (d₆ -DMSO) δ 6.40 (1H, d, J=7.3), 5.93 (1H, d, J=7.3), 4.86 (2H,s), 4.79 (2H, s), 3.67 (3H, s), 2.15 (3H, s).

Methyl[3-amino-1,2-dihydro-2-oxo-6-phenyl-1-pyridyl]acetate (50f), wasisolated (86%) as a grey solid: mp. 207-9° C.; IR (KBr) 3473, 3345,1750, 1644, 1600, 1536, 1443, 1366, 1309, 1212, 1184, 1156; ¹ H NMR (d₆-DMSO) δ 7.30 (5H, m), 6.54 (1H, d), 6.03 (1H, d), 5.25 (2H, s), 4.49(2H, s), 3.61 (3H, s).

Methyl[3-amino-1,2-dihydro-2-oxo-1-pyridyl]acetate (50 g), was obtainedas a colorless oil and used immediately in the next step.

2(S) Methyl2-methyl-[3-amino-6-benzyl-1,2-dihydro-2-oxo-1-pyridyl]acetate (50 h),was isolated (69%) as a colorless oil: IR (film) 3354, 1743, 1646, 1600,1548, 1494, 1455, 1309, 1268, 1227, 113; ¹ H NMR (C₆ D₆) δ 7.29-6.76(5H, m), 5.86 (1H, d, J=7.2), 5.51 (1H, d, J=7.2), 4.43 (1H, q, J=6.7),3.69 (2H, s), 3.41 (2H, s), 3.36 (3H, s), 1.43 (3H, d, J=6.7).

    ______________________________________                                        3 #STR134##                                                                   4 #STR135##                                                                          R.sub.1     R.sub.2   R.sub.3                                          ______________________________________                                        (a)      Ph(CH.sub.2).sub.2 CO                                                                       H         (S)Me                                        (b)      Ph(CH.sub.2).sub.2 CO                                                                       CH.sub.2 Ph                                                                             H                                            (c)      Ph(CH.sub.2).sub.2 CO                                                                       (CH.sub.2).sub.2 Ph                                                                     H                                            (d)      Ph(CH.sub.2).sub.2 CO                                                                       nBu       H                                            (e)      Ph(CH.sub.2).sub.2 CO                                                                       Me        H                                            (f)      Ph(CH.sub.2).sub.2 CO                                                                       ph        H                                            (g)      Ph(CH.sub.2).sub.2 CO                                                                       H         H                                            (h)      Ph(CH.sub.2).sub.2 CO                                                                       CH.sub.2 Ph                                                                             (S)--Me or                                                                    (R,S)--Me                                    (i)      AcTyr         CH.sub.2 Ph                                                                             H                                            (j)      Ph(CH.sub.2).sub.2 SO.sub.2                                                                 CH.sub.2 Ph                                                                             H                                            (k)      Ph(CH.sub.2).sub.2 OCO                                                                      CH.sub.2 Ph                                                                             H                                            (1)      Ph(CH.sub.2).sub.3 CO                                                                       CH.sub.2 Ph                                                                             H                                            ______________________________________                                    

2(S) Methyl 2-[1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl]-propionate (51a). 3-Phenylpropionyl chloride (1.5 g, 9mmol) was added dropwise to a stirred mixture of 2Smethyl-2-[3-amino-1,2-dihydro-2-oxo-1-pyridyl]propionate (50a) (1.63 g,8.33 mmol), dioxane (60 ml), water (15 ml) and sodium bicarbonate (1.54g, 16.7 mmol). The mixture was kept for 1 h then extracted with ethylacetate. The extracts were washed with aqueous sodium bicarbonate, dried(MgSO₄) and concentrated. The resulting red oil was purified by flashchromatography to afford 2.54 g (93%) of an oil: [α]_(D) ²⁰ -68° C. (1,CH₂ Cl₂); IR (CH₂ Cl₂) 3369, 1747, 1690, 1650, 1602, 1512, 1267, 1260,1217; ¹ H NMR (CDCl₃) δ 8.41 (1H, dd), 8.36 (1H, s), 7.24 (5H, m), 7.02(1H, dd), 6.32 (1H, t), 5.44 (1H, q), 3.75 (3H, s), 3.03 (2H, t), 2.70(2H, t), 1.66 (3H, d). FAB M+=329 (M+1), 197, 165, 131, 110, 91.

The following compounds were prepared in a similar manner:

Methyl[6-benzyl-1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl]-acetate(51b), was isolated (93%) as crystals: mp. 95-7° C.; IR (KBr) 3265,1747, 1686, 1642, 1590, 1563, 1511, 1454, 1401, 1220, 1183, 1133; ¹ HNMR (CDCl₃) δ 8.39 (1H, d, J=7.7), 8.27 (1H, s), 7.21 (10H, m), 6.17(1H, d, J=7.7), 4.70 (2H, s), 3.89 (2H, s), 3.67 (3H, s), 3.02 (2H, m),2.70 (2H, m).

Methyl[1,2-dihydro-2-oxo-6-phenylethyl-3-(3-phenylpropionyl)amino-1-pyridyl]-acetate(51c), was isolated (81%) as colorless crystals: mp. 105-8° C.; IR (KBr)3378, 1746, 1680, 1646, 1597, 1517, 1221; ¹ H NMR (CDCl₃) δ 8.34 (1H, d,J=7.7), 8.25 (1H, s), 7.23 (10H, m), 6.11 (1H, d, J=7.7), 4.77 (2H, s),3.78 (3H, s), 2.88 (8H, m).

Methyl[6-butyl-1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl]-acetate(51d), was isolated (88%) as colorless crystals: mp. 84-5° C.; IR (KBr)3345, 2958, 2930, 1756, 1693, 1650, 1602, 1510, 1227, 1180, 1137; ¹ HNMR (CDCl₃) δ 8.34 (1H, d, J=7.7), 8.22 (1H, s), 7.26 (5H, m), 6.12 (1H,d, J=7.7), 4.80 (2H, s), 3.79 (3H, s), 3.03 (2H, t), 2.68 (2H, t), 2.50(2H, t), 1.46 (4H, m), 0.95 (3H, t)

Methyl[1,2-dihydro-6-methyl-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl]-acetate(51e), was isolated (100%) as a pale yellow oil: IR (film) 3264, 1745,1691, 1644, 1587, 1566, 1518, 1495, 1400, 1215, 1183, 1136; ¹ H NMR(CDCl₃) δ 8.33 (1H, d, J=7.6), 7.26 (5H, m), 6.13 (1H, d, J=7.6), 4.83(2H, s), 3.79 (3H, s), 3.03 (2H, m), 2.69 (2H, m), 2.28 (3H, s)

Methyl[1,2-dihydro-2-oxo-6-phenyl-3-(3-phenylpropionyl)amino-1-pyridyl]-acetate(51f), was isolated (99%) as a pale yellow oil: IR (film) 3365, 3299,1751, 1689, 1643, 1600, 1563, 1519, 1493, 1419, 1370, 1224; ¹ H NMR(CDCl₃) δ 8.46 (1H, d, J=7.7), 8.32 (1H, s), 7.32 (10H, m), 6.24 (2H, d,J=7.7), 4.57 (2H, s), 3.73 (3H, s), 3.06 (2H, m), 2.72 (2H, m).

Methyl [1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl]-acetate(51 g), was isolated (81%) as an oil: IR (film) 3330, 1753, 1689, 1650,1600, 1560, 1517, 1374, 1225, 1208; ¹ H NMR (CDCl₃) δ 8.43 (1H, dd,J=7.4, 1.7), 8.33 (1H, s), 7.28 (5H, m), 6.92 (1H, dd, J=6.9, 1.7), 6.29(1H, t), 4.67 (2H, s), 3.79 (3H, s), 3.04 (2H, m), 2.70 (2H, m). MS FAB(+) M+=315 (M+1).

2(S) Methyl2-methyl-[6-benzyl-1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl]-acetate(51 h), was isolated (93%) as a colorless oil; [α]_(D) ³⁰ -19° (c 1, CH₂Cl₂); IR (film) 3354, 3313, 3028, 2950, 1745, 1687, 1645, 1600, 1567,1514, 1454, 1225; ¹ H NMR (CDCl₃) δ 8.35 (1H, d, J=7.5), 8.26 (1H, s),7.27 (10H, m), 6.20 (1H, d, J=7.5), 4.65 (1H, q, J=6.8), 3.99 (2H, s),3.71 (3H, s), 3.03 (2H, m), 2.68 (2H, m), 1.31 (3H, d, J=6.8).

Methyl[3-(N-acetyl-O-benzyl-L-tyrosine)amino-6-benzyl-1,2-dihydro-2-oxo-pyridyl]acetate(51i). A stirred mixture of methyl[3-amino-6-benzyl-1,2-dihydro-2-oxo-1-pyridyl]acetate (100 mg, 0.367mmol), Boc-Tyr(Bn)--OH (136 mg, 0.367 mmol), dimethylformamide (1 ml),diisopropylethylamine (0.25 ml, 1.468 mmol) and2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate(118 mg, 0.367 mmol) was kept overnight at room temperature. The mixturewas diluted with ethyl acetate, washed twice with 1M hydrochloric acid,twice with aqueous sodium bicarbonate, once with brine, then dried(MgSO₄) and concentrated. The residue was purified by flashchromatography (10% ethyl acetate/dichloromethane) to afford a 162 mg(70%) of a colorless oil. The oil (160 mg, 0.255 mmol) was dissolved indichloromethane (1 ml) and treated with trifluoroacetic acid (1 ml) at0° C. The resulting solution was allowed to reach room temperatureduring 40 min then evaporated to dryness at 30° C. The residue wasdissolved in dichloromethane then evaporated to dryness again. Thisprocedure was repeated three times. The residue was dissolved inpyridine (0.5 ml) and treated with acetic anhydride (0.03 ml, 0.3 mmol)at 0° C. The resulting mixture was allowed to reach room temperature andkept for 3.5 h. It was diluted with ethyl acetate, washed twice with 1Mhydrochloric acid, twice with aqueous sodium bicarbonate, dried (MgSO₄)and concentrated to afford 128 mg (86%) of a colorless oil: IR (film)3290, 1751, 1649, 1602, 1568, 1513, 1455, 1438, 1375, 1224, 1179; ¹ HNMR (CDCl₃) δ 8.78 (1H, s), 8.33 (1H, d, J=7.6), 7.33 (8H, m), 7.11 (4H,m), 6.86 (2H, d, J=8.5), 6.47 (1H, d, J=7.6), 6.12 (1H, d, J=7.6), 4.99(2H, s), 4.85 (1H, m), 4.69 (2H, s), 3.87 (2H, s), 3.62 (3H, s), 3.08(2H, m), 1.96 (3H, s).

Methyl[6-benzyl-1,2-dihydro-2-oxo-3-(2-phenylethanesulphonyl)amino-1-pyridyl]-acetate(51j). 2-Phenylethanesulphonyl chloride (Zhong et al., J. Am. Chem.Soc., 113, pp. 2259-63 (1991)) was added to a stirred mixture of methyl[3-amino-6-benzyl-2-oxo-1,2-dihydro-1-pyridyl]-acetate (49b) (1.0 g,3.67 mmol), dichloromethane (15 ml) and triethylamine (1.0 ml, 7.34mmol). The mixture was kept overnight then poured into ethyl acetate.The resulting mixture was washed twice with aqueous sodium bicarbonate,three times with 1M hydrochloric acid, then brine. It was dried (MgSO₄)and concentrated. The resulting pale brown solid was purified by flashchromatography (10% ethyl acetate/dichloromethane) to afford 1.25 g(77%) of a pale yellow solid: m.p. 92-4° C.; IR (KBr) 3181, 1737, 1646,1595, 1565, 1454, 1241, 1220, 1150; ¹ H NMR (CDCl₃) δ 7.53 (1H, d,J=7.5), 7.29 (10H, m), 6.10 (1H, d, J=7.5), 4.75 (2H, s), 3.89 (2H, s),3.67 (3H, 6), 3.34 (2H, m), 3.14 (2H, m).

Methyl [6-benzyl-1,2-dihydro-2-oxo-3-(4-phenylbutyryl)amino-1-pyridyl]-acetate (511), was isolated (74%) as colorlesscrystals: mp. 93-95° C.; IR (KBr) 3285, 1747, 1683, 1642, 1591, 1563,1512, 1455, 1220, 1181; ¹ H NMR (CDCl₃) δ 8.39 (1H, d, J=7.6), 8.24 (1H,s), 7.2 (10H, m), 6.18 (1H, d, J=7.6), 4.7 (2H, s), 3.90 (2H, s), 3.67(3H, s), 2.69 (2H, t), 2.40 (2H, t), 2.04 (2H, m). ##STR136##

2(S)2-[1,2-Dihydro-2-oxo-3-(3-phenylpropionyl)amino)-1-pyridyl]propionicacid (52a). 1M Sodium hydroxide (15 ml, 15 mmol) was added to a stirredsolution of 2(S) methyl2-[1,2-dihydro-2-oxo-3(3-phenylpropionyl)amino-1-pyridyl]propionate(51a) (2.39 g, 7.3 mmol) in methanol (30 ml) at 0° C. The mixture waskept at this temperature for 2 h, acidified with 1M hydrochloric acid(15.1 ml) and extracted with ethyl acetate. The extracts were washedwith brine, dried (MgSO₄) and concentrated to afford 1.98 g (87%) of acolorless solid: [α]_(D) ²⁰ -75° (1, CH₂ Cl₂) ; IR (KBr) 3301, 1724,1693, 1637, 1563, 1523, 1453, 1233, 1216, 765; ¹ H NMR (CDCl₃) δ 8.47(2H, m), 7.20 (5H, m), 7.03 (1H, d), 6.36 (1H, t), 5.35 (1H, q), 3.01(2H, m), 2.70 (2H, m), 1.69 (3H, m).

The following compounds were prepared in a similar manner:

[6-Benzyl-1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl]aceticacid (52b), was isolated (100%) as a pale amber oil: IR (film) 3291,1738, 1686, 1644, 1591, 1554, 1519, 1496, 1454, 1403, 1215, 1182; ¹ HNMR (CDCl₃) δ 8.44 (1H, d, J=7.8), 8.4 (1H, s), 7.21 (10H, m), 6.19 (1H,d, J=7.8), 4.71 (2H, s), 3.90 (2H, s), 2.99 (2H, m), 2.71 (2H, m).

[1,2-Dihydro-2-oxo-6-phenylethyl-3-(3-phenylpropionyl)amino-1-pyridyl]acetic acid (52c), was isolated (94%) as a beige solid:mp. 214-6° C.; IR (KBr) 3289, 1740, 1680, 1640; ¹ H NMR (d₆ -DMSO) δ9.24 (1H, s), 8.14 (1H, d, J=7.7), 7.22 (10H, m), 6.11 (1H, d, J=7.8),4.78 (2H, s), 2.81 (8H, m)

[6-Butyl-1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl]aceticacid (52d), was isolated (99%) as a pale brown solid: mp. 132-4° C.; IR(KBr) 3286, 1739, 1676, 1641, 1584, 1555, 1535, 1455, 1414, 1249, 1227,1204; ¹ H NMR (CDCl₃) δ 8.42 (1H, d, J=7.8), 8.37 (1H, s), 7.24 (5H, m),6.19 (1H, d, J=7.8), 4.82 (2H, s), 3.55 (1H, s), 3.00 (2H, t), 2.67 (2H,t), 2.53 (2H, t), 1.41 (4H, m), 0.94 (3H, t).

[1,2-Dihydro-6-methyl-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl]aceticacid (52e), was isolated as a solid (100%): mp. 159-61° C.; IR (KBr)3335, 1731, 1686, 1642, 1536, 1516, 1430, 1420, 1401, 1222, 1195; ¹ HNMR (d₆ -DMSO) δ 9.21 (1H, s), 8.13 (1H, d, J=7.6), 7.20 (5H, m), 6.15(1H, d, J=7.6), 4.77 (2H, s), 2.87 (2H, m), 2.70 (2H, m), 2.25 (3H, s).

[1,2-Dihydro-2-oxo-6-phenyl-3-(3-phenylpropionyl)amino-1-pyridyl]aceticacid (52f), was isolated (100%) as a pale yellow foam: IR (KBr) 3271,1747, 1683, 1634, 1580, 1536, 1490, 1406, 1392, 1365, 1235, 1219; ¹ HNMR (CDCl₃) δ 8.52 (1H, d, J=7.7), 7.31 (10H, m), 6.48 (2H, s), 6.30(1H, d, J 7.7), 4.60 (2H, s), 3.03 (2H, m), 2.71 (2H, m).

[1,2-Dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl]acetic acid (52g), was isolated (94%) as a colorless solid: mp. 195-7° C.; IR (KBr)3324, 1724, 1693, 1644, 1569, 1555, 1512, 1427, 1370, 1240; ¹ H NMR (d₆-DMSO) δ 9.31 (1H, s), 8.23 (1H, d, J=6.8), 7.36 (1H, dd, J=6.8, 1.71),7.25 (5H, m), 6.25 (1H, t), 4.66 (2H, s), 2.84 (4H, m).

2(R,S)2-[6-Benzyl-1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl]-propionicacid (52 h), was prepared by hydrolysis of compound 51 h in aqueoustetrahydrofuran during 5 h at 40° C. to afford (95%) as a yellow oil: IR(film) 3330, 1734, 1686, 1643, 1600, 1587, 1553, 1524, 1498, 1208; ¹ HNMR (d₆ -DMSO) δ 9.29 (1H, s), 8.18 (1H, d, J=7.6), 7.21 (10H, m), 6.22(1H, d, J=7.6), 4.82 (1H, q, J=6.6), 4.08 (2H, m), 2.76 (4H, m), 1.05(3H, d, J=6.6).

[3-(Acetyl-Tyr(Bn))amino-6-benzyl-1,2-dihydro-2-oxo-1-pyridyl]aceticacid (52i), was isolated (93%) as a foam: IR (KBr) 3302, 1731, 1646,1603, 1562, 1512, 1454, 1428, 1379, 1231, 1178; ¹ H NMR (CDCl₃) δ 9.48(1H, s), 8.36 (1H, d, J=7.6), 7.30 (8H, m), 7.10 (2H, m), 6.85 (2H, d,J=8.3), 6.91 (2H, d, J=8.3), 6.71 (1H, d, J 7.6), 4.95 (1H, m), 4.90(2H, s), 4.68 (2H, s), 3.92 (2H, s), 3.17-2.83 (2H, m), 1.92 (3H, s).

[6-Benzyl-1,2-dihydro-2-oxo-3-(2-phenylethanesulphonyl)amino-1-pyridyl]aceticacid (52j), was isolated (100%) as a colorless solid: mp. 165-7° C.; IR(KBr) 3174, 1760, 1646, 1593, 1567, 1497, 1453, 1424, 1326, 1225, 1140,1127; ¹ H NMR (d₆ -DMSO) δ 13.09 (1H, s), 9.08 (1H, s), 7.30 (11H, m),6.02 (1H, d), 4.68 (2H, s), 4.99 (2H, s), 3.29 (2H, m), 3.03 (2H, m).

[6-Benzyl-1,2-dihydro-2-oxo-3-(2-phenylethoxy)carbonylamino-1-pyridyl]acetic acid (52k), was prepared (70%) byhydrolysis of compound 49i during 1 h at 60° C.: IR (CH₂ Cl₂) 1797,1689, 1649, 1601, 1512, 734; ¹ H NMR (CDCl₃) δ 8.39 (1H, s), 8.03 (1H,d), 7.81 (1H, s), 7.33-7.07 (10H, m), 6.13 (1H, d, J=7.8), 4.72 (2H, s),4.33 (2H, t, J=7.0), 3.86 (2H, s), 2.93 (2H, t, J=7.0).

[6-Benzyl-1,2-dihydro-2-oxo-3-(4-phenylbutyryl)amino-1-pyridyl]aceticacid (521), was isolated (100%) as a white foam: m.p. 159-161° C.; IR(KBr) 3373-3310, 1787, 1726, 1691, 1649, 1599, 1567, 1517, 1367, 1215; ¹H NMR (CDCl₃) δ 8.43 (1H, d, J=7.7), 8.25 (1H, s), 7.37-7.09 (10H, m),6.21 (1H, d, J=7.7), 4.73 (2H, s), 4.15 (3H, s), 3.91 (2H, s), 2.67 (2H,t), 2.39 (2H, t), 2.02 (2H, m). ##STR137##

2(S), N-3(S) 2-[1,2-Dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl]-N-(2-benzyloxy-5-oxotetrahydrofuran-3-yl)propionamide(53a). Tri-n-butyltin hydride (1.7 ml, 6.3 mmol) was added dropwise to astirred mixture of2(S)-2-[1,2-dihydro-2-oxo-3(3-phenylpropionyl)amino-1-pyridyl]propionicacid (52a) (1.1 g, 3.49 mmol), 3(S), 2(R,S)3-allyloxycarbonylamino-2-benzyloxy-5-oxotetrahydrofuran (1.02 g, 3.49mmol; Chapman, Biorg. Med. Chem. Lett., 2, pp. 613-18 (1992)),bis(triphenylphosphine)palladium (II) chloride (55 mg), dichloromethane(35 ml) and dimethylformamide (1 ml). The resulting mixture was stirredfor 5 min. then 1-hydroxybenzotriazole (946 mg, 7 mmol) was added. Themixture was cooled to 0° C. before the additionof-1-(3-dimethylaminopropyl)-2-ethylcarbodiimide hydrochloride (740 mg,3.84 mmol). The mixture was kept overnight at room temperature thenpoured into ethyl acetate. The mixture was washed twice with 1Mhydrochloric acid, twice with aqueous sodium bicarbonate, then brine.The mixture was dried (MgSO₄) and concentrated. The residue wastriturated with pentane. The remaining solid was purified by flashchromatography (40-60% ethyl acetate/hexane) to afford 1.28 g (73%) ofcolorless solid: IR (KBr) 1796, 1692, 1647, 1595, 1557, 1512, 1119; ¹ HNMR (d₆ -DMSO) δ 9.28, 9.26 (1H, 2×s), 8.77, 8.69 (1H, 2×d), 8.24, 8.20(1H, 2×dd), 7.20 (11H, m), 6.31, 6.26 (1H, 2×t), 5.65 (0.5H, d), 5.46(0.5H, d), 5.41, 5.28 (1H, 2×q), 4.7 (2.5H, m), 4.24 (0.5H, t), 3.24(2H, m), 2.80 (4H, m), 1.51, 1.46 (3H, 2×d).

The following compounds were prepared in a similar manner:

N(3(S))2[6-Benzyl-1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl]-N-(2-benzyloxy-5-oxotetrahydrofuran-3-yl)acetamide(53b), was obtained (86%) as a foam: IR (KBr) 3345, 3297, 1807, 1791,1688, 1679, 1650, 1602, 1554, 1525, 1497, 1453, 1372, 1257, 1119; ¹ HNMR (d₆ -DMSO) δ 9.25 (0.5H, s), 9.23 (0.5 H, s), 8.75 (0.5 H, d,J=6.5), 8.67 (0.5H, d, J=7.4), 8.18 (1H, 2d), 7.21 (15H, m), 6.07 (1H,2d), 5.65 (0.5H, d, J=5.0), 5.38 (0.5H, s), 4.83-4.45 (4.5H, m), 4.19(0.5H, m), 3.94, 3.83 (2H, m), 3.10-2.31 (6H, m).

N(3(S))2[1,2-Dihydro-2-oxo-6-phenylethyl-3-(3-phenylpropionyl)amino-1-pyridyl]-N-(2-benzyloxy-5-oxotetrahydrofuran-4-yl)acetamide(53c), was obtained, (74%) as a mixture of anomers: ¹ H NMR (d₆ -DMSO) δ9.71 (1H, d), 9.41 (0.5H, d), 9.25 (0.5H, d), 8.64 (1H, d, J=7.7), 7.75(15H, m), 6.61 (1H, 2d), 6.11 (0.5H, d), 5.93 (0.5H, s), 5.17 (5H, m),4.77 (0.5H, m), 3.68-2.94 (2H, m), 3.32 (8H, m).

N(3(S))2[6-Butyl-1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl]-N-(2-benzyloxy-5-oxotetrahydrofuran-3-yl)acetamide (53d), was obtained (74%) as a mixtureof anomers: IR (KBr) 3300, 1791, 1689, 1645, 1597, 1566, 1546, 1514,1454, 1417, 1378; ¹ H NMR (CDCl₃) δ8.38 (1H, d, J=7.7), 8.13 (1H, s),7.30 (10H, m), 6.18 (1H, t), 5.47 (0.5H, d, J=5.2), 5.43 (0.5H, s), 4.75(4.5H, m), 4.38 (0.5H, m), 3.08-2.35 (8H, m), 1.43 (4H, m), 0.95 (3H,t).

N(3(S))2[1,2-Dihydro-6-methyl-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl]-N-(2-benzyloxy-5-oxotetrahydrofuran-3-yl)acotamide(53e), was obtained (67%) as a mixture of anomers: IR (KBr) 3282, 1774,1667, 1651, 1596, 1561, 1556, 1498, 1265, 1254, 1236, 1199, 1143; ¹ HNMR (d₆ -DMSO) δ9.17 and 9.15 (1H, 2×s), 8.89 (0.5H, d, J=6.5), 8.73(0.5H, d, J=7.4), 7.25 (10H, m), 6.13 (1H, t), 5.64 (0.5H, d, J=5.0),5.45 (0.5H, s), 4.89-4.61 (4.5H, m), 4.26 (0.5H, m), 3.17-2.36 (6H, m),2.23 and 2.15 (3H, 2s).

N(3(S))2-[1,2-Dihydro-2-oxo-6-phenyl-3(3-phenylpropionyl)amino-1-pyridyl]-N-(2-benzyloxy-5-oxotetrahydrofuran-3-yl)acetamide(53f), was obtained (73%) as a mixture of anomers: IR (KBr) 3296, 1792,1691, 1643, 1595, 1561, 1514, 1489, 1453, 1420, 1373, 1230, 1118; ¹ HNMR (d₆ -DMSO) δ9.40, 9.36 (1H, 2s), 8.70 (0.5H, d, J=7.6), 8.52 (0.5H,d, J=7.5), 8.29 (1H, dd), 7.25 (15H, m), 6.20 (1H, d, J=7.6), 5.61(0.5H, d, J=5.0), 5.28 (0.5H, s), 4.78-4.20 (5H, m), 3.12-2.24 (6H, m).

N(3(S)) 2-[1,2-Dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl]-N-(2-benzyloxy-5-oxotetrahydrofuran-3-yl)acetamide(53g), was obtained (70%) as a mixture of anomers: IR (KBr) 3336, 3290,1791, 1691, 1646, 1595, 1582, 1556, 1518, 1454, 1376, 1351, 1150, 1122;¹ H NMR (d₆ -DMSO) δ9.26 (1H, 2s), 8.86 (0.5H, d, J =6.4), 8.67 (0.5H,d, J=7.5), 8.23 (1H, m), 7.40-7.13 (11H, m), 6.24 (1H, 2t, J=7.2), 5.61(0.5H, d, J=5.0), 5.44 (0.5H, s), 4.83-4.59 (2.5H, m), 4.25 (0.5H, m),3.15-2.34 (2H, m), 2.91-2.70 (4H, m). Anal. Calc. for C₂₇ H₂₇ N₃ O₆ H₂O: C, 63.90; H, 5.76; N, 8.28. Found: C 63.70; H, 5.68; N, 8.22. MS FABM⁺ =490 (M+1).

2(R, S), N(3(S))2-[6-Benzyl-1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl]-N(2-benzyloxy-5-oxotetrahydrofuran-3-yl)propionamide(53h), was obtained (89%) as a mixture of diastereomers. Data is givenfor a single diastereomer: IR (film) 3356, 1788, 1677, 1645, 1602, 1517,1455, 1377, 1203, 1167, 1120; ¹ H NMR (CDCl₃) δ8.34 (1H, d, J=7.6), 8.19(1H, s), 7.38-7.13 (10H, m), 6.26 (1H, d, J=7.6), 5.58 (1H, t), 5.31,5.24 (1H, 2×s), 4.62 (2H, 2q), 4.60 (1H, m), 4.27 (1H, m), 2.98, 2.68(4H, 2m), 3.0-2.0 (2H, m)), 1.42 (3H, d).

N(3(5))2-[6-Benzyl-1,2-dihydro-2-oxo-3-(N-acetyl-O-benzyltyrosinyl)amino-1-pyridyl]-N-(2-benzyloxy-5-oxotetrahydrofuran-3-yl)acetamide(53i), was obtained (76%) as a mixture of anomers: IR (KBr) 1794, 1698,1651, 1612, 1514, 1454, 1374, 1247, 1177, 1126; ¹ H NMR (d₆ -DMSO)δ9.34, 9.31 (2×0.5H, 2s), 8.71 (1H, 2d), 8.38 (1H, m), 8.17 (1H, d),7.48-6.88 (19H, m), 6.08 (1H, 2d), 5.65 (0.5H, d, J=5.0), 5.40 (0.5H,9), 5.04 (2H, s), 4.68 (5.5H, m), 4.15 (0.5H, m), 3.95, 3.84 (2H,s+abq), 3.20-2.40 (4H, m), 1.78 (3H, s).

N(3(S))2-[6-Benzyl-1,2-dihydro-2-oxo-3-(2-phenylethanesulphonyl)amino-1-pyridyl]-N-(2-benzyloxy-5-oxotetrahydrofuran-3-yl)acetamide(53j), was obtained (78%) as a mixture of anomers: IR (KBr) 3344, 1792,1691, 1647, 1599, 1566, 1454, 1365, 1150, 1121, 973; ¹ H NMR (d₆ -DMSO)δ9.02, 8.99 (1H, 2s), 8.80 (0.5H, d, J=6.4), 8.70 (0.5H, d, J=7.4), 7.26(15H, m), 6.00 (1H, dd), 5.63 (0.5H, d, J=5.0), 5.39 (0.5H, s), 4.68(4.5H, m), 4.18 (0.5H, m), 3.90 (2H, m), 3.30-2.30 (6H, m).

N(3(S))2-[6-Benzyl-1,2-dihydro-2-oxo-3-(2-phenylethoxy)carbonylamino-1-pyridyl]-N-(2-benzyloxy-5-oxotetrahydrofuran-3-yl)acetamide(53k), was obtained (78%) as a mixture of anomers: IR (KBr) 3386, 1794,1726, 1650, 1603, 1518, 1366, 1214, 699; ¹ H NMR (CDCl₃) δ8.03 (1H, bd),7.63, 7.61 (1H, 2×s), 7.34-7.04 (15H, m), 6.21, 6.18 (1H, 2d), 5.44(0.5H, d, J=5.4), 5.37 (0.5H, s), 4.85, 4.83 (1H, 2d, J=11.6, 11.5),4.61-4.48, 4.32 (4H, 2m), 4.4 (2H, t), 4.08, 4.03 (2H, 2bs), 3.07-2.78(3H, m), 2.47-2.30 (1H, m).

N(3(S))2-[6-Benzyl-1,2-dihydro-2-oxo-3-(4-phenylbutyryl)amino-1-pyridyl]-N-(2-benzyloxy-5-oxotetrahydrofuran-3-yl)acetamide (53l), was obtained (86%)as a colorless oil: IR (CH₂ Cl₂) 1797, 1689, 1649, 1601, 1512, 734; ¹ HNMR (CDCl₃) δ8.42, 8.40 (1H, 2d, J=7.6), 7.35-7.07 (15H, m), 6.21, 6.19(1H, 2d, J=7.6), 5.44 (0.5H, d), 5.37 (0.5H, s), 4.84, 4.81 (1H, 2d,J=11.7, 11.4), 4.73-4.48, 4.34 (4H, 2m), 4.05 (2H, m), 3.05-2.63,2.46-2.30 (6H, 2m), 2.01 (2H, m).

    ______________________________________                                        5 #STR138##                                                                   6 #STR139##                                                                          R.sub.1    R.sub.2    R.sub.3                                          ______________________________________                                        (a)      Ph(CH.sub.2).sub.2 CO                                                                      H          (S)Me                                        (b)      Ph(CH.sub.2).sub.2 CO                                                                      CH.sub.2 Ph                                                                              H                                            (c)      Ph(CH.sub.2).sub.2 CO                                                                      (CH.sub.2).sub.2 Ph                                                                      H                                            (d)      Ph(CH.sub.2).sub.2 CO                                                                      nBu        H                                            (e)      Ph(CH.sub.2).sub.2 CO                                                                      Me         H                                            (f)      Ph(CH.sub.2).sub.2 CO                                                                      Ph         H                                            (g)      Ph(CH.sub.2).sub.2 CO                                                                      H          H                                            (h)      Ph(CH.sub.2).sub.2 CO                                                                      CH.sub.2 Ph                                                                              (R,S)--Me                                    (i)      AcTyr        CH.sub.2 Ph                                                                              H                                            (j)      Ph(CH.sub.2).sub.2 SO.sub.2                                                                CH.sub.2 Ph                                                                              H                                            (k)      Ph(CH.sub.2).sub.2 OCO                                                                     CH.sub.2 Ph                                                                              H                                            (l)      Ph(CH.sub.2).sub.3 CO                                                                      CH.sub.2 Ph                                                                              H                                            ______________________________________                                    

3(S), N(2(S))3-(2-(1,2-Dihydro-2-oxo-3-(3-phenylpropionylamino-1-pyridyl)-propionylamino)-4-oxobutanoicacid (54a; F). A mixture of 2(S), N(3(S))2-[1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl]-N(2-benzyloxy-5-oxotetrahydro-furan-3-yl)propionamide53a (1.28 g, 2.5 mmol), methanol (140 ml) ethyl acetate (60 ml) and 10%palladium on carbon (1.4 g) was stirred under an atmosphere of hydrogen.After 2.5 h more catalyst (300 mg) was added and hydrogenation continuedfor 1 h. The mixture was filtered through Celite™ and then refilteredthrough 0.2 μM nylon filter and concentrated. The residual oiltriturated with a mixture of methanol and ether to afford 916 mg (87%)of colorless crystals: mp. 198-200° C.; [a]_(D) ²⁸ -120° (0.1, CH₃ OH);IR (KBr) 3330, 1794, 1688, 1644, 1583, 1556, 1515, 1427; ¹ H NMR (CD₃OD) δ8.28 (1H, d), 7.35 (1H, d), 7.20 (5H, m), 6.36 (1H, t), 5.49 (1H,q), 4.59 (1H, t), 4.25 (1H, m), 2.98, 2.74 (2×2H, 2×m), 2.59 (2H, m),1.57 (3H, d). Anal. Calcd for C₂₁ H₂₃ N₃ O₆ 0.75 H₂ O: C, 59.08; H,5.78; N, 9.84. Found: C 59.24; H, 5.96; N, 9.84. FAB M⁺ =414 (M+1), 297,165, 91.

The following compounds were prepared in a similar manner:

3(S)3-(6-Benzyl-1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl)acetylamino-4-oxobutanoicacid, (54b; M), was isolated (59%) as colorless crystals: mp. 115° C.(decomp);. IR (KBr) 3440, 3297, 1718, 1646, 1598, 1565, 1526, 1496,1260; ¹ H NMR (CD₃ OD) 8.25 (1H, d, J=7.7), 7.25 (1OH, m), 6.15 (1H, 2d,each J=7.7), 4.73 (2H, 2q), 4.59 (1H, m), 4.30 (1H, m), 3.95 (2H, s),2.98 (2h, m), 2.75 (2H, m), 2.8-2.42 (2H, m). Anal. Calcd for C₂₇ H₂₇ N₃O₆. 0.7 H₂ O: C, 64.58; H, 5.70; N, 8.37. Found: C, 64.51; H, 5.63; N,8.38. MS FAB+ M+=490 (M+1).

3(S)3-(1,2-Dihydro-2-oxo-6-phenethyl-3(3-phenylpropionyl)amino-1-pyridyl)acetylamino-4-oxobutanoicacid (54c), was isolated (46%) as a white solid: IR (KBr) 3375, 1694,1643, 1586, 1561, 1515, 1377, 1254, 1188, 1070; ¹ H NMR (CD₃ OD) 8.18(1H, d, J=7.8), 7.22 (10H, m), 6.15 (1H, d, J=7.8), 4.75 (2H, s), 4.58(1H, m), 4.30 (1H, m), 3.01-2.28 (1OH, m); MS FAB+ M+=504 (M+1).

3(S)3-(6-Butyl-1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl)acetylamino-4-oxobutanoicacid (54d), was isolated (90%) as colorless crystals: m.p. 120-5° C.; IR(KBr) 3315, 1784, 1679, 1644, 1589, 1561, 1556, 1520, 1415, 1379, 1186;¹ H NMR (CD₃ OD) 8.22 (1H, d, J=7.8), 7.24 (5H, m), 6.22 (1H, d, J=7.8),4.80 (2H, m), 4.60 (1H, s), 4.28 (1H, m), 2.98 (2H, m), 2.72 (2H, m),2.58 (4H, m), 1.48 (4H, m), 0.97 (3H, t, J=7.1). Anal. Calcd for C₂₄ H₂₉N₃ O₆ 0.5 H₂ O. C, 62.06; H, 6.51; N, 9.05. Found: C, 62.08; H, 6.43; N,9.01. MS FAB+ M+=456 (M+1).

3(S)3-(1,2-Dihydro-6-methyl-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl)acetylamino-4-oxobutanoicacid (54e), was isolated (85%) as a colorless solid: mp. 129-138° C.; IR(KBr) 327, 3294, 1710, 1695, 1682, 1554, 1525, 1379, 1272, 1240; ¹ H NMR(CD₃ OD) δ8.19 (1H, d, J=7.6), 7.19 (5H, m), 6.21 (1H, d, J=7.6), 4.80(2H, m), 4.59 (1H, m), 4.30 (1H, m), 2.98 (2H, m), 2.72 (2H, m),2.80-2.40 (2H, m), 2.30 (3H, s). Anal. Calcd for C₂₁ H₂₂ N₃ O₆. H₂ O: C,58.46; H, 5.84; N, 9.74. Found C: 58.82; H, 60.5; N, 9.42.

3(S)3-(1,2-Dihydro-2-oxo-6-phenyl-3-(3-phenylpropionyl)amino-1-pyridyl)acetylamino-4-oxobutanoicacid (54f), 73% as an off-white solid: m.p. 140° C. (decomp). [α]_(D) ²⁴=-8.5° (c 0.1, MeOH). IR (KBr) 3302, 1796, 1726, 1679, 1643, 1590, 1560,1516, 1490, 1449, 1420, 1398, 1376, 1231; ¹ H NMR (CD₃ OD) δ8.36 (1H,d), 7.49-7.14 (10H, m), 6.27 (1H, dd), 4.54 (3H, m), 4.30 (1H, m), 3.0,2.73 (2×2H, 2×m), 2.7-2.29 (2H, m).

3(S)3-(1,2-Dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl)acetylamino-4-oxobutanoicacid (54g; G), was isolated (73%) as a foam: mp. 140-5° C. (decomp); IR(KBr) 3352, 3314, 1719, 1700, 1668, 1649, 1600, 1559, 1514, 1379, 1261;¹ H NMR (CD₃ OD) δ8.32 (1H, d, J=7.5), 7.19 (6H, m), 6.34 (1H, t),5.1-4.6 (3H, m), 4.32 (1H, m), 2.7 (6H, m). Anal. Calcd for C₂₀ H₂₁ N₃O₆. 0.6H₂ O: C, 58.50, H, 5.45, N, 10.24. Found: C, 58.43, H, 5.35, N.9.85. MS FAB+ M+=400 (M+1).

3(S), N(2(R,S))3-(2-(6-Benzyl-1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl)propionylamino)-4-oxobutanoicacid (54h), was obtained (69%) as a colorless foam: m.p. 120° C.;[α]_(D) ²⁰ -16.0° (c, 0.11, CH₂ Cl₂). IR (KBr) 3315, 1783, 1727, 1666,1644, 1599, 1564, 1517, 1454, 1379; ¹ H NMR (CD₃ OD) δ8.23 (1H, m), 7.27(10H, m), 6.28 (1H, m), 4.84 (1H, m), 4.53 (1H, m), 4.22 (1H, m), 4.10(2H, m), 2.96 (2H, m), 2.72 (2H, m), 2.39 (2H, m), 1.21 (3H, m). Anal.Calcd for C₂₉ H₂₉ N₃ O₆. 1.25H₂ O: C, 63.93, H, 6.03, N, 7.99. Found: C,63.98, H, 5.85, N, 7.86. MS FAB (+) M+=504 (M+1).

3(S)3-(3-(2-Acetyl-L-tyrosinyl)amino-6-benzyl-1,2-dihydro-2-oxo-1-pyridyl)acetylamino-4-oxobutanoicacid (54i), was isolated (79%) as colorless crystals: mp. 193-6° C.(decomp.); IR (KBr) 3284, 1644, 1599, 1565, 1519, 1455, 1429, 1407,1375, 1267, 1251; ¹ H NMR (d₆ -DMSO/CDCl₃) δ8.16 (1H, d, J=7.7), 7.26(5H, m), 7.03 (2H, d, J=8.4), 6.61 (2H, d, J=8.4), 6.03 (1H, d, J=7.7),4.58 (3H, m), 4.44 (1H, m), 4.13 (1H, m), 3.84 (2H, s), 3.07-2.30 (4H,m). Anal. Calcd for C₂₉ H₃₀ N₄ O₈. 2H₂ O: C, 58.19; H, 5.72; N, 9.36.Found: C, 58.11; H, 5.63; N. 9.29. MS FAB+ M+=563 (M+1).

3(S)3-(6-Benzyl-1,2-dihydro-2-oxo-3-(2-phenylethanesulphonyl)amino-1-pydridyl)acetylamino-4-oxobutanoicacid (54j), was isolated (85%) as a colorless solid: mp. 102-5° C.;[α]_(D) ²³ -9.9° (c 0.1, MeOH); IR (KBr) 3452, 3328, 3155, 1719, 1679,1645, 1594, 1567, 1453, 1425, 1357, 1307, 1225, 1148, 1132; ¹ H NMR (CD₃OD) δ7.52 (1H, d, J=7.6), 7.33 (10H, m), 6.12 (1H, d, J=7.6), 4.73 (2H,m)), 4.58 (1H, d, J=3.7), 4.34 (1H, m)), 3.97 (2H, s), 3.29 (2H, m),3.08 (2H, m), 2.75-2.37 (2H, m). Anal. Calcd for C₂₆ H₂₇ N₃ O₇ S. 1.7H₂O: C, 56.14; H, 5.51; N, 7.55. Found: C, 56.20; H, 5.49; N, 7.29. MSFAB+ M+=526 (M+1).

3(S)3-(6-Benzyl-1,2-dihydro-2-oxo-3-(2-phenylethoxy)carbonylamino-1-pyridyl)acetylamino-4-oxobutanoicacid (54k), was isolated (54%) as an off-white solid: mp. 84-86° C.; IR(KBr) 3373-3310, 1787, 1726, 1691, 1649, 1599, 1567, 1517, 1367, 1215; ¹H NMR (CD₃ OD) δ7.93 (1H, bd, J=7.4), 7.37-7.18 (10H, m)), 6.15 (1H, d,J=7.4), 4.77 (1H, d, J=3.7), 4.67 and 4.58 (2H, 2m), 4.35 (2H, t,J=6.9), 4.35 (1H, m), 3.94 (2H, s), 2.98 (2H, t, J=6.9), 2.76-2.39 (2H,m).

3(S)3-(6-Benzyl-1,2-dihydro-2-oxo-3-(4-phenylbutyryl)carbonylamino-1-pyridyl)acetylamino-4-oxobutanoicacid (54l), was isolated (50%) as a white solid: mp. 89-93° C.; IR (KBr)3369-3302, 1678, 1645, 1594, 1565, 1517, 1379, 1258; ¹ H NMR (d₄-methanol) δ8.25 (1H, d, J=7.6), 7.37-7.18 (10H, m), 6.15 (1H, d,J=7.4), 4.74 (2H, m), 4.60 (1H, m), 4.30 (1H, m), 3.97 (2H, s),2.76-2.37 (2H, m), 2.67 (2H, t), 2.45 (2H, t), 1.98 (2H, m)). Anal.Calcd for C₂₈ H₂₉ N₃ O₆. 1.5H₂ O: C, 63.39; H, 6.08, N, 7.92. Found C:63.69; H, 5.74; N, 7.83.

    ______________________________________                                        7 #STR140##                                                                   8 #STR141##                                                                   R.sub.1              R.sub.2     R.sub.3                                      ______________________________________                                        (a)                                                                                 9 #STR142##        H           H                                        (b)                                                                                 0 #STR143##        --CH.sub.2 --Ph                                                                           H                                        ______________________________________                                    

t-ButylN-2-(3-benzyloxycarbonylamino-1,2-dihydro-2-oxo-1-pyridyl)acetyl-3-amino-5-(2,6-dichlorobenzoyloxy)-4-oxo-pentanoate(56a). The acetic acid (55a) (WO 93 21213) in THF (2 ml) was stirred atroom temperature and treated with 1-hydroxybenzotriazole (60 mg, 0.448mmol) and dimethylaminopropyl-3-ethylcarbodiimide hydrochloride (47 mg,0.246 mmol). After 5 mins water (2 drops) was added and stirringcontinued for 20 minutes. Bis(triphenylphosphine) palladium II chloride(6 mg) was added followed by a solution of t-butyl3-(allyloxycarbonylamino)-4-oxo-5-(2,6-dichlorobenzoyl-oxy)pentanoate(WO 93 16710) (103 mg, 0.224 mmol) in THF (1 ml). Tributyltin hydride(0.09 ml, 0.336 mmol) was added dropwise over 1 hour at roomtemperature. The mixture was stirred for a further 3 hours and pouredonto ethyl acetate, washed with 1 M HCl, aqueous NaHCO₃, brine, driedover MgSO₄ and concentrated in vacuo. The residue was triturated withpentane and the supernatant discarded. The remaining solid was purifiedby flash chromatography (50% ethyl acetate/hexane) to afford the titlecompound 92 mg (63%) as a colorless oil: [α]_(D) ²⁶ -29.6° (C 1.1, CH₂Cl₂); IR (film) 3377, 3365, 3332, 3312, 1733, 1691, 1650, 1599, 1515,1366, 1261, 1153, 1068, 747; ¹ H NMR (CDCl₃) δ8.09 (1H, d, J=6.8), 7.84(1H, s), 7.58 (1H, d, J=8.3), 7.33 (8H, m), 7.02 (1H, dd, J=6.9, 1.7),6.33 (1H, t, J=7.2), 5.20 (2H, s), 5.12 (2H, m), 4.89 (1H, dt), 4.65(2H, m), 2.80 (2H, m), 1.38 (9H, s).

t-ButylN-2-(6-benzyl-1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl)acetyl-3-amino-5-(2,6-dichlorobenzyloxy)-4-oxo-pentanoate(56b), was prepared by the method described for (56a) which afforded thetitle compound (66%) as a colorless oil: IR (film) 3364, 3313, 1738,1688, 1648, 1600, 1566, 1514, 1433, 1369, 1254, 1152; ¹ H NMR (CDCl₃)δ8.40 (1H, d, J 7.6), 8.30 (1H, s), 7.28 (13H, m), 6.20 (1H, d, J=7.6),5.12 (2H, q), 4.86 (1H, m), 4.65 (2H, q), 4.06 (2H, s), 3.07-2.61 (6H,m), 1.39 (9H, s).

    ______________________________________                                        1 #STR144##                                                                   2 #STR145##                                                                   R.sup.1              R.sup.2     R.sup.3                                      ______________________________________                                        (a)                                                                                 3 #STR146##        H           H                                        (b)                                                                                 4 #STR147##        --CH.sub.2 --Ph                                                                           H                                        ______________________________________                                    

N-2(3-Benzyloxycarbonylamino-1,2-dihydro-2-oxo-1-pyridyl)acetyl-3-amino-5-(2,6-dichlorobenzoyloxy)-4-oxo-pentanoicacid (57a; Q). The ester (56a) (210 mg, 0.356 mmol) in dichloromethane(0.5 ml) was cooled to 0° C. and treated with trifluoroacetic acid (0.5ml), stirred and warmed to 20° C. over 30 minutes. The solution wasevaporated to dryness under reduced pressure, redissolved indichloromethane and concentrated (×3). The residue was triturated withethyl acetate and diluted with ether to afford the title compound 162 mg(85%) as a colorless solid: m.p. 165-8° C. (decomposition); [α]_(D) ²³-38.8° (c 0.1, CH₃ OH); IR (KBr) 3332, 3275, 1723, 1658, 1649, 1597,1581, 1562, 1526, 1432, 1385, 1258, 1218, 1206; ¹ H NMR (d₆ -DMSO) δ8.96(1H, d, J=7.3), 8.34 (1H, s), 7.85 (1H, dd, J=7.3), 7.58 (3H, m), 7.35(5H, m), 6.29 (1H, t, J=7.3), 5.26 (2H, m), 5.15 (2H, s), 4.69 (3H, m),2.75 (2H, m). Anal. Calcd. C₂₇ H₂₃ N₃ O₉ Cl₂ : C, 53.66; H, 3.84; N,6.95. Found: C, 53.36; H, 3.90; N, 6.81. M.S. (+FAB); 604 (M⁺ +1), 285,241, 195, 173, 149, 91.

N-2-(6-Benzyl-1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl)acetyl-3-amino-5-(2,6-dichlorobenzoyloxy)-4-oxo-pentanoicacid (57b; P), was prepared by the method described for 57a whichafforded the title compound (78%) as colorless crystals: m.p. 116-120°C. (decomposition); [α]_(D) ²⁶ -41.10 (c 0.1, CH₃ OH); IR (KBr) 3299,1739, 1715, 1689, 1666, 1645, 1598, 1563, 1518, 1432, 1209, 1151; ¹ HNMR (d₆ -DMSO) δ9.24 (1H, s), 8.88 (1H, d, J=7.6), 8.18 (1H, d, J=7.7),7.60 (3H, m), 7.26 (10H, m), 6.06 (1H, d, J=7.7), 5.23 (2H, ABq), 4.69(3H, m), 3.93 (2H, s), 2.78 (6H, m). Anal. Calcd. for C₃₅ H₃₁ N₃ O₈ Cl₂.H₂ O: C, 59.16; H, 4.68; N, 5.91. Found: C, 59.38; H, 4.53; N, 5.84.M.S. (+FAB); 694, (Cl=35, 37), (M⁺ +1); 692 (Cl=35, 35), (M⁺ +1).##STR148##

(3S, 4R,S) t-ButylN-(benzyloxycarbonyl)-3-amino-4-(2-benzoxazolyl)-4-hydroxy-butanoate(59). To a stirred solution of benzoxazole (250.2 mg, 2.1 mmol) inanhydrous THF (10.5 ml) at -78° C. under N₂ was added 2.3 M n-butyllithium in hexanes (0.96 ml, 2.2 mmol) dropwise. After stirring at -78°C. for 20 min, dry MgBr₂ OEt₂ (594.0 mg, 2.3 mmol) was added as a solid.The resulting heterogeneous mixture was warmed to -45° C. and stirredfor 15 min. The reaction mixture was then recooled to -78° C. and asolution of aldehyde 58 (Graybill et al., Int. J. Peptide Protein Res.,44, pp. 173-182 (1993)) (644.6 mg, 21 mmol) in THF (10.5 ml) was addeddropwise.

The reaction was stirred at -78° C. for 30 min, warmed to 0° C. for 1 h,and then stirred at room temperature for 16 h. The reaction was quenchedwith 5% sodium bicarbonate (2.0 ml) and the THF was removed in vacuo.The resulting aqueous residue was extracted four times with methylenechloride. The combined extracts were washed with brine, dried (MgSO₄),filtered and reduced in vacuo to give 880.0 mg of crude product. Flashchromatography (45:55 ethyl acetate/hexane) afforded 567.2 mg (63%) ofthe title compound, an oil, as a mixture of diastereoisomers at C-4. IR(film) 3324, 2976, 1726, 1517, 1455, 1368, 1243, 1159, 1048, 747; ¹ HNMR (CDCl₃) δ7.71-7.64 (1H, m), 7.52-7.48 (1H, m) 7.37-7.20 (7H, m),5.91 (1H, brd, J=9.0), 5.79 (1H, d, J=9.0), 5.41-4.78 (4H, m), 4.75-4.54(1H, m), 2.91-2.51 (2H, m), 1.42 (9H, s), 1.37 (9H, s).

(3S, 4R,S) t-Butyl 3-amino-4-(2-benzoxazolyl)-4-hydroxybutanoate (60). Asolution of the ester 59 (189.0 mg, 0.44 mmol) in ethanol (5.0 ml) wastreated with 10% Palladium on carbon (20.5 mg) and stirred under anatmosphere of H₂ for 21 h. The mixture was filtered through Celite®, andthe solvent was evaporated to afford 125.0 mg (98%) of crude amine 60 asan oil. This was used without further purification. ¹ H NMR (CDCl₃)δ7.73-7.64 (1H, m), 7.51-7.42 (1H, m), 7.35-7.22 (2H, m), 6.48 (3H,brs), 5.58 (1H, d, J=3.0), 5.27 (1H, d, J=6.5), 4.23-4.05 (1H, m),2.92-2.63 (2H, m), 1.36 (9H, s), 1.33 (9H, s).

(3S, 4R,S) t-ButylN-(N-benzyloxycarbonyl-(S)-valinyl-(S)-alaninyl)-3-amino-4-(2-benzoxazolyl)-4-hydroxybutanoate(61). A solution of the amine 60 (261.4 mg, 0.89 mmol), Z-Val-Ala-OH(286.9 mg, 0.89 mmol) (prepared by standard peptide syntheticprocedures) and hydroxybenzotriazole (120.3 mg, 0.89 mmol) in DMF (3.0ml) at 0° C. was treated with 1-ethyl-3-[3-(dimethylamino)propyl]carbodiimide hydrochloride (179.2 mg, 0.93 mmol). The reactionwas warmed to room temperature and stirred for 16 h. The reaction wasdiluted with ethyl acetate and washed twice with 1 M sodiumhydrogensulphate, twice with saturated sodium bicarbonate, then water,and brine. The organic layer was dried (MgSO₄), filtered and reduced invacuo to afford 494.8 mg of crude product. Flash chromatography (95:5methylene chloride/methanol) gave 480.9 mg (91%) of the title compoundas a yellow solid: mp. 81-83° C.; IR (KBr) 3312, 2974, 1723, 1709, 1529,1455, 1368, 1243, 1156, 747; ¹ H NMR (CDCl₃) δ7.79 (0.5H, d, J=8.0),7.73-7.20 (9.5H, m), 6.15 (1H, t, J=8.5), 5.74 (0.5H, brd, J=5.5), 5.45(1H, brd, J=7.5), 5.28-5.20 (0.5H, m), 4.82-4.11 (3.5H, m), 4.78-4.55(1H, m), 4.40-4.22 (1H, m), 2.95-2.51 (2H, m), 2.12-1.95 (1H, m),1.45-1.32 (12H, m), 1.11-0.81 (6H, m), ¹³ C NMR (CDCl₃) δ173.14, 172.94,171.82, 171.03, 170.78, 165.98, 165.45, 157.29, 157.17, 151.23, 151.10,140.92, 140.82, 136.83, 136.79, 128.91, 128.52, 125.75, 124.97, 120.60,120.40, 111.38, 81.82, 81.68, 70.27, 68.97, 67.44, 60.43, 50.74, 50.55,49.18, 49.07, 36.87, 36.57, 32.37, 28.51, 19.88, 19.80, 18.53. Anal.Calcd. for C₃₁ H₄₀ N₄ O₈. H₂ O: C, 60.57; H, 6.89; N, 9.11. Found: C,60.84; H, 6.64; N, 9.09. M.S. (+FAB); 597 (M⁺ +1); 541, 91.

(3S) t-ButylN-(N-benzyloxycarbonyl-(S)-valinyl-(S)-alaninyl)-3-amino-4-(2-benzoxazolyl)-4-oxobutanoate(62). The alcohol 61 (100.3 mg, 0.17 mmol) was dissolved in methylenechloride (2.0 ml) and Dess-Martin reagent (142.6 mg, 0.34 mmol) wasadded (Ireland et al., J. Org. Chem., 58, p. 2899 (1993); Dess et al.,J. Org. Chem., 48, pp. 4155-4156 (1983)). The resulting mixture wasstirred for 22 min and then partitioned between saturated sodiumthiosulphate: saturated sodium bicarbonate (1:1, 10 ml), and ethylacetate (10 ml). The resulting organic phase was washed with saturatedsodium thiosulphate, saturated sodium bicarbonate (1:1), saturatedsodium bicarbonate, and brine. The organic phase was dried (MgSO₄),filtered and reduced in vacuo to give 111.3 mg of crude product. Flashchromatography (95:5 methylene chloride/methanol) afforded 97.3 mg (96%)of the title compound as an oil: [α]_(D) ²³ -11.74° (c 0.95, CH₂ Cl₂);IR (CH₂ Cl₂) 3419, 2974, 1721, 1677, 1501, 1369, 1221, 1156; ¹ H NMR(CDCl₃) δ7.89-7.84 (1H, m), 7.73-7.22 (10H, m), 5.98 (1H, d, J=9.0),5.72 (1H, m), 5.10 (2H, q, J=12.5), 4.73 (2H, m), 4.20 (1H, dd, J=7.0,8.5), 3.30 (1H, dd, J=5.0, 16.5), 3.03 (1H, dd, J=5.5, 16.5), 2.18-1.97(1H, m), 1.39 (3H, d, J=7.0), 1.34 (9H, s), 0.93 (3H, d, J=6.0), 0.90(3H, d, J=6.0), ¹³ C NMR (CDCl₃) δ186.46, 172.73, 171.90, 170.13,157.17, 156.28, 151.16, 140.99, 136.99, 129.39, 129.08, 128.66, 128.59,126.49, 123.06, 112.55, 82.73, 67.60, 60.84, 53.75, 49.41, 38.58, 32.05,28.52, 19.85, 19.32, 18.51. M.S. (+FAB); 595 (M⁺ +1); 539, 91.

(3S)N-(N-Benzyloxycarbonyl-(S)-valinyl-(S)-alaninyl)-3-amino-4-(2-benzoxazolyl)-4-oxobutanoate(63; Q). A solution of the ester 62 (95.0 mg, 0.16 mmol) in a 1:1mixture of methylene chloride and trifluoroacetic acid (10.0 ml) wasstirred for 1 h under a dry atmosphere of N₂. The solution was thenreduced in vacuo, taken up in ether and reduced again. This process wasrepeated six times to afford the crude product as an off white solid.Flash chromatography (95:5 methylene chloride/methanol) gave 60.0 mg(69%) of the title compound as a white solid. The product existed as amixture of three isomers in CD₃ OD, consisting of the ketone form (oneisomer, c 44%), and its acyloxy ketal form (two isomers at C-4, c. 56%):m.p. 156-159° C. [α]_(D) ²⁶ -45.6° (c 0.13, methanol); IR (KBr) 3440,2967, 1713, 1703, 1638, 1531, 1427; ¹ H NMR (CD₃ OD) δ7.93-7.24 (9H, m),5.59 (1H, brt), 5.16-5.00 (2H, m), 5.0-4.78 (1H, m), 4.50-4.22 (1H, m),3.95-3.81 (1H, m), 3.11 (2H, d, J=6.5), 3.05-2.92 (1H, m), 2.70-2.39(1H, m), 2.08-1.89 (1H, m), 1.19-0.78 (9H, m). Anal. Calcd. for C₂₇ H₃₀N₄ O₈. 0.5H₂ O: C, 59.22; H, 5.71; N, 10.23. Found: C, 59.48, H, 5.36,N, 10.17. M.S. (+FAB); 539 (M⁺ +1), 91. ##STR149##

7-Methoxybenzoxazole (65a). A mixture of 2-nitro-6-methoxyphenol (2.62g, 15.5 mmol) (EP 333176) and 10% Palladium on carbon (130 mg) inethanol (50.0 ml) was stirred under an atmosphere of H₂ for 75 min. Themixture was filtered through Celite® then immediately treated withp-toluenesulphonic acid (32.0 mg) and triethylorthoformate (6.45 ml,38.8 mmol) then heated under reflux under an atmosphere of N₂. After 20h p-toluenesulphonic acid (30.0 mg) and triethylorthoformate (6.45 ml,38.8 mmol) were added. After a total of 44 h heating, the reaction wasallowed to cool and reduced in vacuo. The resulting residue was purifiedby flash chromatography (25:75 ethyl acetate/hexane) to give 1.97 g(85%) of the title compound as a yellow solid: m.p. 28-31° C.; IR (film)1629, 1497, 1434, 1285, 1097; ¹ H NMR (CDCl₃) δ8.09 (1H, s), 7.40 (1H,d, J=8.0), 7.28 (1H, t, J=8.0), 6.89 (1H, d, J=8.0), 4.02 (3H, s); ¹³ CNMR (CDCl₃) δ152.84, 145.82, 142.50, 139.99, 125.75, 113.42, 108.80,56.97. Anal. Calcd. for C₈ H₇ N₁ O₂. 0.1H₂ O: C, 63.65; H, 4.81; N,9.29. Found: C, 63.43, H, 4.88, N, 9.05. M.S. (+FAB); 150 (M⁺ +1).

4-Methoxybenzoxazole (65b). To a suspension of 4-hydroxybenzoxazole(2.00 g, 14.8 mmol) (Musser et al., J. Med. Chem., 30, pp. 62-67 (1987))in acetone (80.0 ml) was added dried K₂ CO₃ (2.25g, 16.3 mmol) followedby iodomethane (1.38 ml, 22.2 mmol). The reaction was heated underreflux under N₂ for 4.5 h, then filtered and reduced in vacuo to affordthe crude product. The resulting residue was purified by flashchromatography (25:75 ethyl acetate/hexane) to give 2.0 g (91%) of thetitle compound as a white crystalline solid: m.p. 72-74° C.; IR (KBr)3089, 1619, 1610, 1503, 1496, 1322, 1275, 1090, 1071, 780, 741; ¹ H NMR(CDCl₃) δ8.02 (1H, s), 7.32 (1H, t, J=8.0), 7.18 (1H, d, J=8.0), 6.81(1H, d, J=8.0), 4.04 (3H, s). Anal. Calcd. for C₉ H₇ NO₂ : C, 64.42; H,4.73; N, 9.39. Found: C, 64.40; H, 4.84; N, 9.31; m/z (EI) 149 (M⁺ +1,100%).

(3S, 4R,S) t-ButylN-(allyloxycarbonyl)-3-amino-4-hydroxy-4-(2-(7-methoxybenzoxazolyl))butanoate(66a). To a stirred solution of 7-methoxybenzoxazole 65a (548.6 mg, 3.68mmol) in anhydrous THF (18.5 ml) at -78° C. under N₂ was added 1.56 Mn-butyl lithium in hexanes (2.47 ml, 3.86 mmol) dropwise, to produce ayellow colored solution. After stirring at -78° C. for 20 min, dry MgBr₂OEt₂ (1.045g, 4.05 mmol) was added as a solid. The resultingheterogeneous mixture was warmed to -45° C. and stirred for 15 min. Thereaction mixture was then recooled to -78° C. and a solution of(S)-Alloc-Asp(t-Bu)H^(1b) (946.4 mg, 3.68 mmol) in THF (18.5 ml) wasadded dropwise. The reaction was stirred at -78° C. for 30 min, warmedto 0° C. and stirred for 1 h. The resulting homogeneous reaction waswarmed to room temperature and stirred for 16 h. The reaction wasquenched with 5% sodium bicarbonate (3.5 ml) then THF was removed invacuo. The resulting aqueous residue was extracted with methylenechloride (×6). The combined extracts were washed with brine, dried(MgSO₄), filtered and reduced in vacuo to give 1.8 g of crude product.Flash chromatography (40:60 ethyl acetate/hexane) gave 1.21 g (81%) ofthe title compound, an oil, as a mixture of diastereoisomers at C-4: IR(CH₂ Cl₂) 3425, 2983, 1725, 1504, 1290, 1157, 1101; ¹ H NMR (CDCl₃)δ7.35-7.19 (2H, m), 6.89-6.81 (1H, m), 6.00-5.57 (2H, m), 5.32-5.05 (3H,m), 4.68-4.35 (3H, m), 4.01 (3H, s), 2.86-2.59 (2H, m), 1.45 (9H, s),1.41 (9H, s); ¹³ C NMR (CDCl₃) δ171.18, 171.09, 165.80, 165.30, 156.71,156.60, 145.65, 142.76, 142.71, 140.82, 140.72, 133.23, 125.81, 125.72,118.41, 118.21, 113.07, 112.87, 108.95, 82.16, 70.28, 69.98, 66.52,66.39, 57.03, 52.57, 52.29, 37.83, 36.86, 28.65. Anal. Calcd. for C₂₀H₂₆ N₂ O₇. 0.6H₂ O: C, 57.57; H, 6.57; N, 6.72. Found: C, 57.49, H,6.34, N, 6.60. M.S. (+FAB); 407 (M⁺ +1); 351, 307, 154.

(3S, 4R,S) t-ButylN-(allyloxycarbonyl)-3-amino-4-hydroxy-4-(2-(4-methoxybenzoxazolyl))butanoate(66b), was prepared according to the method described for 66a whichafforded 1.29 g (26%, 68% based on recovered starting material) of thetitle compound as an oil and as a mixture of diastereoisomers at C-4: IR(CH₂ Cl₂) 3400, 1725, 1625, 1505, 1369, 1354, 1281, 1263, 1226, 1158,1092, 1048; ¹ H NMR (CDCl₃) δ7.34-7.24 (1H, m), 7.16 (1H, d, J=8.2),6.79 (1H, d, J=7.9), 6.00-5.50 (2H, m), 5.30-5.05 (3H, m), 4.70-4.35(4H, m), 4.02 (3H, s), 2.90-2.45 (2H, m), 1.45-1.41 (9H, 2×s). Anal.Calcd. for C₂₀ H₂₆ N₂ O₇. 0.4H₂ O: C, 58.07; H, 6.53; N, 6.77. Found: C,58.09; H, 6.41; N, 6.63. M.S. (+FAB); 407 (M⁺ +1, 88%); 351 (100).

(3S, 4R,S) t-ButylN-(N-acetyl-(S)-(O-tert-butyltyrosinyl)-(S)-valinyl-(S)-alaninyl)-3-amino-4-hydroxy-4-(2-(7-methoxybenzoxazolyl))butanoate(67a). To a stirred solution of the benzoxazole 66a (481.9 mg, 1.19mmol) and Ac-Tyr(^(t) Bu)-Val-Ala-OH (586.3 mg, 1.30 mmol) in methylenechloride (3.5 ml) and DMF (3.5 ml) was added bis(triphenylphosphine)palladium (II) chloride (18.0 mg), followed by tributyltinhydride (0.80ml, 2.96 mmol) dropwise. Hydroxybenzotriazole (320.4 mg, 2.37 mmol) wasadded and the mixture cooled to 0° C.1-Ethyl-3-[3-(dimethylamino)propyl]carbodiimide hydrochloride (278.2 mg,1.42 mmol) was added and the mixture was allowed to warm to roomtemperature and stirred for 16.5 h. The reaction was diluted with ethylacetate and washed twice with 1 M sodium hydrogensulphate, twice withsaturated sodium bicarbonate, water, and brine. The organic layer wasdried (MgSO₄), filtered and reduced in vacuo to yield 2.0 g of crudeproduct. Flash chromatography (95:5 methylene chloride/methanol) gave844.0 mg (94%) of the title compound as a white solid: m.p. 205° C.; IR(KBr) 3399, 3304, 2977, 1729, 1643, 1506, 1367, 1290, 1161; ¹ H NMR (d₆-DMSO) δ8.24-7.78 (4H, m), 7.43-7.32 (2H, m), 7.23 (2H, d, J=8.5), 7.16-7.07 (1H, m), 6.93 (2H, d, J=8.5), 6.52, 6.40 (1H, 2×d, J=5.5,J=5.0), 5.03, 4.78-4.49, 4.45-4.16 (5H, brt, 2×m), 4.05, 4.04 (3H, 2×s),3.08-2.35 (14H, m), 2.11-1.89 (1H, m), 1.83 (3H, s), 1.49-1.32, 1.15,1.0-0.81 (27H, s, 2×m, J=7.0); ¹³ C NMR (d₆ -DMSO) δ175.55, 175.18,173.88, 173.75, 173.05, 169.23, 157.28, 148.55, 146.16, 143.21, 136.63,133.55, 128.87, 127.17, 115.78, 111.92, 84.02, 81.50, 71.40, 61.15,60.05, 57.79, 53.39, 51.62, 43.76, 40.52, 34.58, 32.52, 31.60, 26.35,23.11, 22.71, 21.76. Anal. Calcd. for C₃₉ H₅₅ N₅ O₁₀. 0.5H₂ O: C, 61.40;H, 7.40; N, 9.18. Found: C, 61.43; H, 7.31; N, 9.07. M.S. (+FAB); 754(M⁺ +1); 698, 338, 267.

(3S, 4R,S) t-ButylN-(N-acetyl-(S)-(O-tert-butyl-tyrosinyl)-(S)-valinyl-(S)-alaninyl)-3-amino-4-hydroxy-4-(2-(4-methoxybenzoxazolyl))butanoate(67b), was prepared according to the method described for 67a whichafforded 1.05 g (94%) of the title compound as a fine white powder: m.p.210-213° C. (dec); IR (KBr) 3284, 2977, 1736, 1691, 1632, 1536, 1505,1452, 1392, 1367, 1258, 1236, 1161, 1091; ¹ H NMR (d₆ -DMSO) δ8.20-7.75(4H, m), 7.40-7.10 (4H, m), 7.00-6.80 (3H, m), 6.45, 6.34 (1H, 2×d,J=5.3, J=5.0), 5.00-4.10 (5H, m), 4.00, 3.99 (3H, 2×s), 3.00-2.25 (4H,m), 1.95 (1H, m), 1.78 (3H, s), 1.39-0.80 (27H, m). Anal. Calcd. for C₃₉H₅₅ N₅ O₁₀. 0.5H₂ O: C, 61.40; H, 7.40; N, 9.18. Found: C, 61.58; H,7.38; N, 8.91. M.S. (+FAB); 754 (M⁺ +1, 30%) ; 72 (100).

(3S) t-ButylN-(N-acetyl-(S)-(O-tert-butyl-tyrosinyl)-(S)-valinyl-(S)-alaninyl)-3-amino-4-(2-(7-methoxybenzoxazolyl))-4-oxobutanoate(68a). The Dess-Martin reagent (1.082 g, 2.55 mmol) (Ireland et al., J.Org. Chem., 58, p. 2899 (1993); Dess et al., J. Org. Chem., 48, pp.4155-4156 (1983)) was added to a stirred suspension of the alcohol 67a(641.0 mg, 0.85 mmol) in methylene chloride (46.0 ml). The resultingmixture was stirred for 1 h before being partitioned between saturatedsodium thiosulphate: saturated sodium bicarbonate (1:1, 86.0 ml) andethyl acetate (86.0 ml). The resultant organic phase was washed in turnwith saturated sodium thiosulphate: saturated sodium bicarbonate (1:1),saturated sodium bicarbonate, and brine. The organic phase was dried(MgSO₄), filtered and reduced in vacuo to give 660.0 mg of crudeproduct. Flash chromatography (94:6 methylene chloride/methanol) gave636.0 mg (100%) of the title compound as a white solid: m.p. 209° C.;[α]D²⁴ -21.8 ° (c 0.16, methanol); IR (KBr) 3395, 3294, 2977, 1722,1641, 1535, 1505, 1161; ¹ H NMR (CDCl₃) δ8.43-8.16 (1H, m), 7.97-7.62(2H, m), 7.49-7.14 (3H, m), 7.08-6.95 (3H, m), 6.89-6.73 (2H, m),5.81-5.68 (1H, m), 5.16-4.86 (2H, m), 4.53 (1H, brt), 4.03 (3H, s),3.16-2.84 (4H, m), 2.11-1.84 (4H, m), 1.46-1.14 (21H, m), 0.92-0.78 (6H,m); ¹³ C NMR (CDCl₃) δ186.28, 173.39, 171.90, 171.19, 171.03, 169.89,156.43, 154.75, 146.32, 142.88, 140.98, 132.31, 130.54, 126.98, 124.73,114.95, 111.42, 82.44, 78.71, 58.92, 57.20, 54.91, 53.47, 48.77, 39.43,38.15, 32.79, 29.44, 28.60, 23.55, 20.27, 19.70, 19.34. M.S. (+FAB); 752(M⁺ +1); 696, 336, 265.

(3S) t-ButylN-(N-acetyl-(S)-(O)-tert-butyl-tyrosenyl)-(S)-valinyl-(S)-alaninyl)-3-amino-4-(2-(4-methoxybenzoxazolyl))-4-oxobutanoate(68b), was prepared according to the method described for the ketone 68awhich afforded 420 mg (55%) of the title compound as a white solid: m.p.211-213° C. (dec); [α]_(D) ²⁴ -23.9° (c 0.82, methanol); IR (KBr) 3277,3075, 1723, 1690, 1632, 1530, 1506, 1392, 1366, 1269, 1234, 1160, 1094;¹ H NMR (CDCl₃) δ8.15 (1H, brs), 7.7 (2H, brs), 7.46 (1H, t, J=8.3),7.24 (2H, d, J=8.3), 7.10 (1H, brs), 7.03 (2H, d, J=8.3), 6.83 (3H, m),5.74 (1H, q, J=6.9), 5.00 (2H.sub., m), 4.51 (1H, t, J=7.0), 4.07 (3H,s), 3.20-2.95 (4H, m), 2.00 (4H, m), 1.42 (3H, d, J=6.8), 1.35 (9H, s),1.23 (9H, s), 0.86 (6H, d, J =6.7). M.S. (+FAB); 752 (M⁺ +1, 7%); 72(100).

(3S)N-(N-Acetyl-(S)-tyrosinyl-(S)-valinyl-(S)-alaninyl)-3-amino-4-(2-(7-methoxybenzoxazolyl))-4-oxobutanoate(69a; R). A solution of the ester 68a (600.0 mg, 0.80 mmol) in a 1:1mixture of methylene chloride and trifluoroacetic acid (65.0 ml) wasstirred for 1 h under a dry atmosphere of N₂. The solution was thenreduced in vacuo, taken up in ether and reduced again This process wasrepeated six times to afford the crude product as an off white solid.Flash chromatography (gradient 95:5 to 80:20 methylenechloride/methanol) gave 420.8 mg (83%) of the title compound as ahygroscopic white solid. The product existed as a mixture of threeisomers in CD₃ OD, consisting of the keto form (c 50%), and itsacycloxy, keto form (two isomers at C-4, c 50%): m.p. decomposes above150° C.; [α]_(D) ²⁴ -33.2° (c 0.17, methanol); IR (KBr) 3300, 1715,1658, 1650, 1531, 1517, 1204; ¹ H NMR (CD₃ OD) δ7.46-7.19 (2H, m),7.16-6.91 (3H, m), 6.70-6.59 (2H, m), 5.62-5.49 (1H, m), 5.00-4.72 (1H,obscurred m), 4.69-4.51 (1H, m), 4.49-4.08 (2H, m), 4.05-3.89 (3H, m),3.16-2.47 (4H, m), 2.05-1.78 (4H, m), 1.41-1.11, 1.05-0.70 (9H, 2×m) .Anal. Calcd. for C₃₁ H₃₇ N₅ O₁₀. 3H₂ O: C, 53.67; H, 6.25; N, 10.10.Found: C, 53.76; H, 5.56; N, 10.28. M.S. (+FAB); 640 (M⁺ +1); 435, 147.

(3S) t-ButylN-(N-acetyl-(S)-tyrosinyl-(S)-valinyl-(S)-alaninyl)-3-amino-4-(2-(4-methoxybenzoxazolyl))-4-oxobutanoate(69b; 2), was prepared according to the method described for the acid69a which afforded the hygroscopic title compound 252 mg (96%). Theproduct existed as a mixture of three isomers in CD₃ OD, consisting ofthe keto form, and its acyloxy ketal form (two isomers at C-4). Theproduct existed as a single isomer in d-6 DMSO: m.p. 200-203° C. (dec.);[α]_(D) ²⁴ -38.0° (c 0.23, methanol); IR (KBr) 3289, 2968, 1718, 1713,1658, 1634, 1548, 1517, 1506, 1461, 1453, 1393, 1369, 1268, 1228, 1174,1092; ¹ H NMR (d₆ -DMSO) δ9.20 (1H, brs), 8.71 (1H, d, J=6.2), 8.10 (2H,m), 7.83 (1H, d, J=8.7), 7.61 (1H, t, J=8.2), 7.46 (1H, d, J=8.2), 7.08(3H, m), 6.65 (2H, d, J=8.3), 5.50 (1H, q, J=6.5), 4.50 (1H, m), 4.37(1H, m), 4.20 (1H, m), 4.05 (3H, s), 3.09-2.77 (4H, m), 1.94 (1H, m),1.79 (3H, s), 1.23 (3H, d, J=7.0), 0.82 (6H, m). Anal. Calcd. for C₃₁H₃₇ N₅ O₁₀. 1.5H₂ O: C, 55.85; H, 6.05; N. 10.51. Found: C, 55.21; H,5.69; N, 10.13. M.S. (+FAB) ; 640 (M⁺ +1, 22%); 107 (100). ##STR150##

3S) t-ButylN-(allyloxycarbonyl)-3-amino-4-oxo-5-(1,2-dioxo-2-phenylethyloxy)-pentanoate(80). Potassium fluoride (792 mg, 13.6 mmol) and then benzoyl formicacid (1.02 g, 6.82 mmol) were added to a stirred solution of (3S)t-butyl N-(allyloxycarbonyl)-3-amino-5-bromo-4-oxo-pentanoate (WO 9316710) (2.17 g, 6.20 mmol) in dimethylformamide (30 ml). The mixture wasstirred for 140 mins, quenched with water (50 ml) and extracted withethyl acetate (2×50 ml). The combined organic extracts were washed withwater (4×50 ml) then brine (50 ml). They were dried (MgSO₄) andconcentrated to afford an oil which was purified by flash chromatography(20-45% ethyl acetate in hexane) to afford 2.44 g (94%) of a colorlessoil: [α]_(D) ²⁰ -35.0° (c 1.41, CH₂ Cl₂); IR (film) 3359, 2981, 2938,1752, 1740, 1726, 1712, 1512, 1369, 1285, 1177, 1053, 991, 939, 688; ¹ HNMR (CDCl₃) δ8.15 (2H, m), 7.66 (1H, m), 7.53 (2H, m), 5.90 (2H, m),5.33 (2H, m), 5.31 (1H, d, J=16.9), 5.18 (1H, d, J=16.9), 4.63 (3H, m),3.03 (1H, dd, J=17.3, 4.6), 2.74 (1H, dd, J=17.3, 4.9), 1.44 (9H, s). MS(C.I.) 420 (M⁺ +1 20%); 364 (100).

(3S) t-Butyl N-(allyloxycarbonyl)-3-amino-5-hydroxy-4-oxo-pentanoate(81). A mixture of the ester 80 (2.40 g, 5.71 mmol), tetrahydrofuran(200 ml) and 1 M aqueous potassium bicarbonate (200 ml) was vigorouslystirred at room temperature for 18 h. The layers were separated and theaqueous portion extracted with ethyl acetate (100 ml). The combinedorganic extracts were washed with brine (100 ml), dried (MgSO₄) andconcentrated. The residue was purified by flash chromatography (10-60%ethyl acetate in hexane) to afford 1.48 g (90%) of pale yellow oil:[α]_(D) ²⁰ -5.9° (c 1.06, CH₂ Cl₂); IR (film) 3345, 2981, 2936, 1739,1725, 1712, 1692, 1515, 1368, 1259, 1158, 1051; ¹ H NMR (CDCl₃) δ5.92(2H, m), 5.30 (2H, m), 4.36-4.69 (5H, m), 3.05 (1H, dd, J=17.4, 4.3),2.93 (1H, t), 2.70 (1H, dd, J=17.4, 4.9), 1.43 (9H, s). Anal. Calcd forC₁₈ H₂₁ N₁ O₆. 0.25H₂ O: C, 53.51; H, 7.43; N, 4.80. Found: C, 53.61; H,7.18; N, 4.71. MS (C.I.) 280 (M⁺ +1, 87%); 232 (100).

(33) t-ButylN-(allyloxycarbonyl)-3-amino-5-(2,6-dichlorophenyl-methoxy)-4-oxo-pentanoate(82). A stirred mixture of alcohol 81 (1.44 g, 5.01 mmol),2,6-dichlorobenzyl iodide (Abraham et al., J. Chem. Soc., pp. 1605-1607(1936)) (4.31 g, 15.0 mmol), silver oxide (2.32 g, 10.0 mmol) anddichloromethane (25 ml) was heated under reflux for 45 h. The mixturewas allowed to cool to room temperature then diluted with water (50 ml)then extracted with ethyl acetate (50 ml, 25 ml). The organic layer waswashed with water (50 ml) then brine (50 ml), dried (MgSO₄), andconcentrated. The residue was purifed by flash chromatography (10-100%ethyl acetate in hexane) to afford 1.65 g (74%) of a colorless oil:[α]_(D) ²⁰ +8.80 (c 1.13, CH₂ Cl₂); IR (film) 3339, 2980, 2935, 1724,1712, 1503, 1438, 1368, 1246, 1156, 1106, 770; ¹ H NMR (CDCl₃) δ7.33(2H, m), 7.22 (1H, dd), 5.92 (2H, m), 5.28 (2H, m), 4.87 (2H, m), 4.67(1H, m), 4.58 (2H, br d), 4.56 (1H, d, J=16.9), 4.31 (1H, d, J=16.9),3.04 (1H, dd, J=16.7, 4.5), 2.77 (1H, dd, J=16.7, 4.9), 1.40 (9H, s).Anal. Calcd. for C₂ OH₂₅ Cl₂ N₁ O₆. 0.25H₂ O: C, 53.28; H, 5.70; N,3.11. Found: C, 53.15; H, 5.52; N, 2.98. M.S. (C.I.); 446 (M+, 27%); 390(100).

(3R, S) t-ButylN-[N-phenylmethyloxycarbonylvalaninyl-alaninyl]-3-amino-5-(2,6-dichlorophenylmethyloxy)-4-oxo-pentanoate(83a). 1-(3-Dimethylamino-propyl)-3-ethylcarbodiimide hydrochloride (379g, 1.98 mmol) and 1-hydroxybenzotriazole (486 mg, 3.60 mmol) were addedto a stirred solution of N-phenyl-methyloxycarbonylvalinylalanine (637mg, 1.98 mmol) in tetrahydrofuran (40 ml) and water (1 ml). The mixturewas stirred for 15 mins and then the ether 82 (802 mg, 1.80 mmol) andbis(triphenylphosphine)palladium (II) chloride (ca 5 mg) were added.

Tributyltin hydride (785 mg, 725 l, 2.70 mmol) was then added dropwiseduring 20 mins and the resulting solution was stirred for 3.75 h andthen quenched with 1 M hydrochloric acid (50 ml). The mixture wasextracted twice with ethyl acetate. The combined organic extracts werewashed with 1 M hydrochloric acid, twice with aqueous sodiumbicarbonate, water and then brine, dried (MgSO₄) and concentrated. Theresidue was purified by flash chromatography (10-30% ethylacetate-dichloromethane) to afford 941 mg (79%) of pale yellow solid:m.p. 148-52° C.; IR (KBr) 3287, 3070, 1730, 1691, 1641, 1536, 1369,1289, 1247, 1156; ¹ H NMR (CDCl₃) δ7.33 (8H, m), 7.23 (1H, dd), 6.61(1H, br, d), 5.42 (1H, br, d), 5.11 (2H, s), 4.85 (3H, m), 4.50 (1H, m),4.40 (1H, d, J=16.9), 4.26 (1H, d, J=16.9), 4.02 (1H, m), 2.99 (1H, dd,J=16.8, 4.7), 2.73 (1H, dd, J=16.8, 5.0), 2.09 (1H, m), 1.37 (12H, m),0.96 (3H, d, J=6.9), 0.91 (3H, d, J=6.8). Anal. Calcd. for C₃₂ H₄₁ Cl₂N₃ O₈. 0.25H₂ O: C, 57.25; H, 6.23; Cl, 10.57; N, 6.26. Found: C, 57.18;H, 6.23; Cl, 10.58; N, 5.95. M.S. (+FAB); 667 (M⁺ 1, 1%); 666 (3), 159(25), 91 (100).

(3R, S) t-ButylN-[(N-acetyl-O-t-butyltyrosinyl)-valaninyl-alaninyl]-3-amino-5-(2,6-dichlorophenylmethyloxy)-4-oxo-pentanoate(83b), was prepared by the method described for 83a to afford 554 mg(64%) of colorless solid: m.p. 184-6° C.; IR (KBr) 3282, 3075, 1736,1690, 1633, 1536, 1508, 1366, 1236, 1161; ¹ H NMR (d₆ -DMSO) δ8.49 (1H,d), 8.14 (1H, d), 8.08 (1H, d), 7.84 (1H, d), 7.43 (3H, m), 7.14 (2H,d), 6.83 (2H, d), 4.71 (2H, 9), 4.51 (2H, m), 4.36 (2H, dd), 4.17 (2H,m), 2.93 (1H, m), 2.73 (1H, m), 1.94 (1H, m), 1.74 (3H, 9), 1.37 (9H,s), 1.23 (12H, m), 0.83 (6H, m). M.S. (+FAB); 793 (M⁺ 1, 4%); 737 (5),681 (1), 178 (40), 159 (45), 136 (100), 107 (40). M.S. (-FAB); 792 (20),791 (40), 447 (100).

(R, S)N-[N-(Phenylmethyloxy)carbonyl-valinyl-alaninyl]-3-amino-5-(2,6-dichlorophenylmethyloxy)-4-oxo-pentanoicacid (84a; V). Trifluoroacetic acid (5 ml) was added to a stirredsolution of the ester 83a, (918 mg, 1.38 mmol) in dichloromethane (20ml). The mixture was stirred for 2.5 h then evaporated to dryness. Theresidue was treated with ether (25 ml) and evaporated to dryness. Thisprocedure was repeated three times. The resulting product was trituratedwith ether (10 ml) and then dried to afford 730 mg (87%) of light brownpowder: m.p. 156-60° C.; IR (KBr) 3282, 2965, 1702, 1694, 1642, 1536,1438, 1246, 1230; ¹ H NMR (d₆ -DMSO) δ8.48 (1H, d), 8.09 (1H, d), 7.47(9H, m), 5.02 (2H, s), 4.70 (2H, s), 4.49 (1H, m), 4.37 (2H, dd), 4.27(1H, m), 3.88 (1H, m), 2.75 (1H, dd), 2.54 (1H, dd), 1.96 (1H, m), 1.19(3H, s), 0.84 (6H, m). Anal. Calcd. for C₂₈ H₃₃ Cl₂ N₃ O₈. 0.5H₂ O: C,54.27; H, 5.53; Cl, 11.45; N, 6.78. Found: C, 54.49; H, 5.39; Cl, 11.33;N, 6.73. M.S. (+FAB); 610 (M⁺ 1, 10%); 91 (100).

(R, S)N-[N-(Acetyl)tyrosinyl-valinyl-alaninyl]-3-amino-5-(2,6-dichlorophenylmethyloxy)-4-oxo-pentanoicacid (84b; W), was obtained as a colorless powder (95%) by the methodused for 84a. m.p. 165-8° C.: IR (KBr) 3295, 2968, 1733, 1642, 1517,1438, 1231, 1105; ¹ H NMR (d₆ -DMSO) 9.2 (1H, br, 8), 8.48 (1H, br, d),8.14 (1H, br, d), 8.02 (1H, br, d), 7.81 (1H, br, d), 7.45 (3H, m), 7.02(2H, d), 6.62 (2H, d), 4.70 (2H, s), 4.12-4.53 (3H, m), 3.60 (3H, m),2.51-2.92 (4H, m), 1.96 (1H, m), 1.75 (3H, s), 1.21 (3H, d), 0.83 (6H,m). Anal. Calcd. for C₃₁ H₃₈ Cl₂ N₄ O₉. H₂ O: C, 53.22; H, 5.76; Cl,10.14; N, 8.09. Found: C, 53.33; H, 5.54; Cl, 10.02; N, 7.85. M.S.(+FAB); 682 (M⁺ 2, 30%); 681 (67), 158 (100). (-FAB); 680 (45), 679(100).

EXAMPLE 6

We obtained inhibition constants (K_(i)) and IC₅₀ values for severalcompounds of this invention using enzyme assays with UV-visiblesubstrate, fluorescent substrate, and cell assays as described inExample 2. The following K_(i) and IC₅₀ values were determined forcompounds 22e, 54b, 54j, 54k, 57b, 85, 86, 87, 88, 89, 90, 91, 92, 98,102a-c, 106a-c, 108a-c, 114a, 114b, 115, 121, 125a, 125b, 126, 127, 128,129, 130, 131, 132a, 132b, 133, 135a, 135b, 136, 137, 138, 139, 140,141, 142, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155,156, 157, 158, 159, 160, 161, 162, and 163 using the indicated assays.The structures of compounds 22e, 54b, 54j, 54k, and 57b are shown inExample 5. The other compound structures are shown in Example 7.

    ______________________________________                                                     Assay                                                                           UV-visible                                                                              Cell                                                 Compound       K.sub.i (μM)                                                                         IC.sub.50 (μM)                                    ______________________________________                                         22e           0.19      >20                                                   54b                     20                                                    54j                     10                                                    54k                     6.6                                                   57b                     2.2                                                   85            0.0035    9.8                                                   86            0.175     4.0                                                   87            7.2       35.0                                                  88            0.9                                                             89            0.018                                                           90            0.42      6.2                                                   91            0.26      >25                                                   92            3.8                                                             98            0.535     4.0                                                  102a                     4.0                                                  102b           0.29      1.75                                                 102c           0.68                                                           106a           2.3       30.0                                                 106b           0.2       2.9                                                  106c           3.8       >30.0                                                108a                     17.5                                                 108b           0.4       25.0                                                 108c           0.43                                                           114a           0.12      3.8                                                  114b           3.7                                                            115            0.345     6.0                                                  121            4.3                                                            125a           0.39      >30.0                                                125b           0.060     0.30                                                 126            0.45      1.5                                                  127            0.39      8.0                                                  128            0.04      7.5                                                  129            0.59      25.0                                                 130                      1.20                                                 131            12.0      30.0                                                 132a           5.0       >30.0                                                132b           12.5                                                           133            50.0      >30.0                                                135a           0.090     0.90                                                 135b           0.32      0.95                                                 136                      1.0                                                  137            0.04      0.25                                                 138                      0.375                                                139            0.350     2.0                                                  140            0.87      >30.0                                                141            0.670                                                          142                      1.75                                                 144            0.32      >20.0                                                145            0.34      8.5                                                  146            0.16      3.8                                                  147            0.26      8.5                                                  148            6.3       30.0                                                 149            14.0      >30.0                                                150            10.0      30.0                                                 151            13.0      30.0                                                 152            8.8                                                            153            0.24                                                           154            0.042     2.4                                                  155            0.023                                                          156            0.001     2.7                                                  157            0.26                                                           158            1.1                                                            159            0.0017    8.0                                                  160            0.145     2.25                                                 161            0.011                                                          162            0.0025                                                         163            0.0028    1.2                                                  ______________________________________                                    

EXAMPLE 7

Compounds 126, 127, 128, 129, 135a, 135b, 137 144, 145, 146, 147, 148,149, 150, 151, 152, 153, 154, 155, 156, 157, 159, 160, 162, and 163 weresynthesized by a method similar to the method used in the synthesis of69a. ##STR151##

Compound 158 was synthesized by a method similar to the method used inthe synthesis of (K). ##STR152##

Compound 130 was synthesized by a method similar to the method used inthe synthesis of 56b. ##STR153##

Compounds 131, 136, 138, and 142 were synthesized by a method similar tothe method used in the synthesis of 57b. ##STR154##

Compounds 132a, 132b, 139, 140, and 141 were synthesized by a methodsimilar to the method used in the synthesis of 47a. The startingmaterial for compound 140 was obtained as described in: Robl, et al., J.Am. Chem. Soc., 116, pp. 2348-2355 (1994). The starting material forcompound 141 was obtained as described in: Wyvratt, et al., Pept.Struct: Funct. Proc. (8th Am. Pept. Symp.), (1983) or U.S. Pat. No.4,415,496. ##STR155##

Compound 133 was synthesized by a method similar to the method used inthe synthesis of 47b. ##STR156##

Compound 161 was synthesized by a method similar to the method used inthe synthesis of 125a. ##STR157##

Compounds 22e, 54b, 54j, 54k, and 57b were synthesized as described inexample 5.

Compounds 85, 86, 87, 88, 89, 90, 91, 92, 98, 102a, 102b, 102c, 106a,106b, 106c, 108a, 108b, 108c, 114a, 114b, 115, 121, 125a, and 125b weresynthesized as follows. ##STR158##

N-(N-Acetyl-tyrosinyl-valinyl-(4(R)-allyloxyprolinyl))-3(S)-amino-4-oxobutanoic acid (85).

Step A. N-tert-Butoxycarbonyl-4(R)-allyloxyproline.N-tert-Butoxycarbonyl(4R)-hydroxyproline (9.25 g, 40 mmol) was added toa solution of 60% sodium hydride (3.36 g, 84 mmol) in 100 ml ofanhydrous tetrahydrofuran and stirred for 2 hours at room temperature.Allyl bromide (6.9 ml, 80 mmol) was added to the mixture and refluxedfor 6 hours. The mixture was quenched with the addition of ice chips,then additional water was added and the mixture was washed with hexane.The aqueous layer was acidified with 10% sodium hydrogen sulfate andextracted with ethyl acetate (2×150 ml). The combined extracts weredried over anhydrous sodium sulfate, filtered and evaporated to give 5 gof the title product with no further purification. ¹ H NMR (CDCl₃ ;exist as rotamers) δ5.92-5.82 (1H, m), 5.3-5.14 (2H, m) 4.5-4.31 (1H,m), 4.16-4.05 (1H, m), 4.04-3.9 (1H, m), 3.79-3.5 (3H, m), 2.43-2.2(1.5H, m), 2.15-2.10 (0.5H, m), 1.45 (4.5H, s), 1.35 (4.5H, s).

Step B. 4(R)-Allyloxyproline methyl eater hydrochloride.N-tert-Butoxycarbonyl-4(R)-allyloxyproline (5 g, 18.4 mmol) was refluxedin 50 ml of saturated methanolic hydrogen chloride for 6 hours. Themixture was evaporated in vacuo to give 3.78 g of a yellow gum as thetitle compound: ¹ H NMR (CDCl₃) δ5.83-5.72 (1H, m), 5.24-5.14 (1H, d),5.13-5.08 (1H, d), 4.55-4.3 (3H, m), 4.25-4.15 (1H, m), 3.9 (1.5H, s),3.78 (1.5H, s), 3.7-3.28 (3H, m), 2.45-2.32 (1H, m), 2.2-2.05 (1H, m).

Step C. N-Acetyl-tyrosinyl-valinyl-(4(R)-allyloxyproline) methyl enter.4(R)-Allyloxyproline methyl ester hydrochloride (1.05 g, 4.75 mmol) andN-acetyl-Tyr-Val-OH (1.68 g, 5.21 mmol) were dissolved in 10 ml of a 1:1mixture of dichloromethane and dimethylformamide and cooled to 0° C.Diisopropylethylamine (1 ml, 5.93 mmol) was added to the cooled mixturefollowed by the addition of N-hydroxybenzotriazole (0.769 g, 5.69 mmol)and 1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (1.18 g,6.2 mmol). After stirring for 2 hours, the mixture was warmed to roomtemperature and stirred for 16 hours. The reaction was poured into 150ml of ethyl acetate and washed with 50 ml each of water, 10% sodiumhydrogen sulfate, and 10% sodium bicarbonate. The organic layer wasdried over sodium sulfate, filtered, and evaporated to give a lightyellow solid. This was purified by flash chromatography eluting withdichloromethane/methanol/pyridine (100:3:0.5) to give 780 mg of thetitle compound. ¹ H NMR (CD₃ OD) δ7.02-6.96 (2H, d), 6.67-6.63 (2H, d),5.95-5.85 (1H, m), 5.34-5.27 (1H, d), 5.16-5.13 (1H, d), 4.53-4.38 (3H,m), 4.28-4.22 (1H, m), 4.12-3.97 (3H, m), 3.82-3.73 (1H, m), 3.72 (3H,s), 3.04-2.88 (2H, m), 2.85-2.72 (2H, m), 2.45-2.34 (1H, m), 2.08-1.95(2H, m), 1.92 (3H, s), 1.00-0.92 (6H, 2×d).

Step D.N-(N-Acetyl-tyrosinyl-valinyl-(4(R)-allyloxyprolinyl))-3(S)-amino-4-oxobutanoicacid tert-butyl ester semicarbazone.N-Acetyl-tyrosinyl-valinyl-(4-allyloxyproline) methyl ester (770 mg,1.57 mmol) was dissolved in 20 ml of tetrahydrofuran and 4 ml ofmethanol. Lithium hydroxide (145 mg, 3.46 mmol) was added to the mixtureand stirred at room temperature. After two hours, 1 ml of 10% hydrogenchloride was added and the mixture evaporated in vacuo to give a solidresidue then partitioned between 5 ml of water and 50 ml of ethylacetate and the organic layer separated and evaporated in vacuo to give430 mg of the acid that was used immediately in the next step.

N-Acetyl-tyrosinyl-valinyl-4-allyloxyproline (420 mg, 0.88 mmol) and3-amino-4-oxobutyric acid tert-butyl ester semicarbazone (184 mg, 0.8mol, Graybill et al., Int. J. Protein Res., 44, pp. 173-82 (1994)) togive 100 mg (20%) of the title compound as a white amorphous solid: ¹ HNMR (CD₃ OD) δ7.24-7.2 (1H, m), 7.04-6.97 (2H, d), 6.73-6.65 (2H, d),5.98-5.86 (1H, m), 5.35-5.24 (1H, d), 5.17-5.12 (1H, m), 4.12-3.98 (2H,m), 3.72-3.67 (1H, m), 2.98-2.92 (3H, m), 2.38-2.32 (1H, m), 2.1-2.02(2H, m), 1.92 (3H, s), 0.98-0.89 (6H, 2×d).

Step E.N-(N-Acetyl-tyrosinyl-valinyl-(4(R)-allyloxyprolinyl))-3(S)-amino-4-oxobutanoicacid (85).N-(N-Acetyl-tyrosinyl-valinyl-(4(R)-allyloxyprolinyl))-3(S)-amino-4-oxobutanoicacid tert-butyl ester semicarbazone (100 mg) was deprotected asdescribed (Example 3, compound K, Step C) to give 44.2 mg (53%) of thetitle compound: ¹ H NMR (CD₃ OD) δ7.04-6.97 (2H, d), 6.72-6.65 (2H, d),5.97-5.86 (1H, m), 5.32-5.25 (1H, d), 5.17-5.12 (1H, d), 4.62-4.40 (3H,m), 4.30-4.13 (2H, m), 4.12-3.96 (3H, m), 3.75-3.68 (1H, m), 2.99-2.92(1H, m), 2.78-2.70 (1H, m), 2.70-2.48 (2H, m), 2.35-2.30 (1H, m),2.17-1.95 (2H, m), 1.92 (3H, s), 0.98-0.88 (6H, 2×d).

Compounds 86 and 87 were prepared by a similar method described for thesynthesis of 69a in example 5: ##STR159##

N-Acetyl-(S)-valinyl-(4-(S)-phenoxy)prolinyl-3(S)-amino-4-(7-methoxybenzoxazol-2-yl)-4-oxo-butanoicacid (86). N-Acetyl-(S)-valinyl-(S)-(4-(S)-phenoxy)proline was convertedto 86 as a white powder: ¹ H NMR (DMSO-d₆) δ8.75(d, 1H), 7.6-7.2(m, 4H),7.0-6.8(m, 4H), 5.5(m, 1H), 5.05(s, 1H), 4.5(t, 1H), 4.29(t, 1H), 4.0(s,3H), 4.0-3.8(m, 2H), 3.0-2.8(dd, 2H), 2.3(m, 1H), 2.09(m, 1H),1.95-1.8(m, 2H), 1.78(s, 3H), 1-0.7(dd, 6H). ##STR160##

N-Acetyl(4-(R)-phenoxy)prolinyl-3(S)-amino-4-(7-methoxybenzoxazol-2-yl)-4-oxo-butanoicacid (87): N-Acetyl-(S)-(4-(S)-phenoxy)proline was converted to 87 as awhite powder: ¹ H NMR (DMSO-d₆) δ9.1(d, 1H), 8.76(d, 1H), 7.6-7.2(m,4H), 7.0-6.9(m, 4H), 5.55(m, 1H), 5.45(m, 1H), 5.0(m, 2H), 4.56(t, 1H),4.40(t, 1H), 4.0(s, 3H), 3.9(dd, 1H), 3.76(d, 1H), 3.64(d, 1H),3.1-2.9(m, 1H), 2.8(m, 1H), 2.50(m, 1H), 2.3-2.2(m, 1H), 2.09(m, 1H),1.95 and 1.75(2×s, 3H, rotamers) ##STR161##

N-2-(6-Benzyl-1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl)acetyl-3(S)-amino-5-hydroxy-4-oxo-pentanoic acid (88).N-2-(6-Benzyl-1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl)acetyl-3(S)-amino-5-hydroxy-4-oxo-pentanoic acid tert-butyl ester wasprepared from 52b and 81 following the method described for thesynthesis of 83a to give a white solid (45%): ¹ H NMR(CDCl₃) δ8.40(d,1H), 8.20(s, 1H), 7.4-7.1(m, 11H), 6.18(s, 1H), 4.72(m, 1H), 4.65-4.5(q,2H), 4.4-4.2(dd, 2H), 4.0(s, 2H), 3.04(t, 2H), 2.9(dd, 1H), 2.76(t, 2H),2.55(dd, 1H), 1.39(s, 9H). The resulting product was converted to 88 bymethod described in example 5, compound 84a to give the title compound(42%) as a white solid: ¹ H NMR(CDCl₃) δ8.5(d, 1H), 8.1(d, 1H), 8.0(m,1H), 7.4-7.1(m, 11H), 6.3(d, 1H), 4.9-4.8(m, 2H), 4.6-4.4(m, 2H),4.3(dd, 1H), 4.1(s, 2H), 3.3(t, 1H), 3.05(t, 2H), 2.8-2.6(m, 3H)

Compounds 89 and 90 were prepared by a similar method described for thepreparation of 84a in example 5. ##STR162##

N-Acetyl-(S)-tyrominyl-(S)-valinyl-(S)-alaninyl-3(S)-amino-5-(2-chlorobenzyloxy)-4-oxo-pentanoic acid (89) was prepared fromAc-Tyr-Val-Ala-OH and (3S) t-butylN-(allyloxycarbonyl)-3-amino-S-(2-chlorophenylmethoxyl)-4-oxo-pentanoate(prepared by a similar method as 82) to give a white solid: ¹ H NMR(DMSO-d₆) δ9.15(s, 1H), 8.5(d, 1H), 7.98(d, 1H), 7.75(d, 1H),7.55-7.3(m, 4H), 7.0(d, 1H), 6.6(d, 2H), 4.6-4.3(m, 6H), 4.3-4.1(m, 2H),2.9(d, 1H), 2.76(dd, 1H), 2.7-2.5(m, 2H), 1.95(m, 1H), 1.75(s, 3H),1.2(d, 3H), 0.9-0.7(dd, 6H) ##STR163##

N-2-(6-Benzyl-1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl)acetyl-3-amino-5-(2-chlorobenzyloxy)-4-oxo-pentanoic acid (90) wasprepared from 52b and (3S) t-butylN-(allyloxycarbonyl)-3-amino-5-(2-chlorophenylmethoxyl)-4-oxo-pentanoate(prepared by a similar method as 82) to give a white solid: ¹ HNMR(DMSO-d₆) δ9.2(s, 1H), 8.75(d, 1H), 7.7-7.1(m, 14H), 6.4(d, 1H),4.65(d, 6H), 4.56(s, 1H), 4.6-4.35(dd, 1H), 3.9(s, 2H), 2.9-2.6(m, 6H)##STR164##

N-2-(6-Benzyl-1,2-dihydro-2-oxo-3-(3-phenylpropionyl)amino-1-pyridyl)acetyl-3(S)-amino-5-(5-(2,6-dichlorophenyl)thiazol-2-yl)-4-oxo-pentanoicacid (91) was prepared from 52b and3-(Allyloxycarbonyl)-amino-4-[(2,6-dichloro-phenyl)-thiazol-2-yl]-4-hydroxy-butyricacid tert-butyl ester (99) as described for the preparation of 69a togive an off-white powder: ¹ H NMR(DMSO-d₆) δ9.32(s, 1H), 9.05(d, 1H),8.27(d, 1H), 8.18(d, 1H), 7.7(d, 1H), 7.6(t, 1H), 7.4-7.1(m 11H), 6.1(d,1H), 5.64(m, 1H), 4.8-4.6(dd, 2H), 3.85(s, 2H), 3.02(m, 1H), 2.9-2.7(m,4H). ##STR165##

3-(S)-(2-(3[3-(S)-(4-Hydroxy-phenyl)-propionylamino]-2-oxo-azepan-1-yl)-acetylamino)-4-oxo-butyricacid (92) was prepared from2-(3[3-(S)-(4-Hydroxy-phenyl)-propionylamino]-2-oxo-azepan-1-yl)-aceticacid and N-allyloxycarbonyl-4-amino-5-benzyloxy-2-oxotetrahydrofuran(Chapman, Biorg. Med. Chem. Lett., 2, pp. 613-18 (1992)) by a similarmethod described for the synthesis of 54a to give the title compound asa white solid: ¹ H NMR(DMSO-d₆) δ9.10-9.20(s, 1H), 8.40(s, 1H), 7.88(d,1H), 7.0(d, 2H), 6.64(d, 2H), 4.60(t, 1H), 4.10(q, 2H), 3.9-4.2(m, 2H),3.6(m, 1H), 3.18(d, 2H), 2.70(t, 2H), 2.40(m, 2H), 1.85-1.40(m, 8H).##STR166##

4-Ethoxymethylene-2-styryl-4H-oxazol-5-one (94) was prepared accordingto Cornforth, The Chemistry of Penicillin, Clarke, Johnson, Robinson,(eds.) Princeton University Press, p. 804 (1949)

4-Oxo-3-(3-phenyl-acryly(amino)-4,6,7,1-tetrahydro-pyrrolo[1,2-a]pyrimidine-(68) -carboxylic acid ethyl ester (95) was prepared from 94by the procedure in example 5 for compound 3 to give 4.5 g (30%) of thetitle compound: ¹ H NMR (CD₃ OD) δ1.3 (t, 3H), 2.35 (m, 1H), 2.65 (m,1H), 3.1 (m, 1H), 3.15 (m, 1H), 4.25 (q, 2H), 5.15 (dd, 1H), 6.95 (d,1H), 7.4 (m, 3H), 7.6 (m, 2H), 7.65 (d, 1H), 8.95 (s, 1H).

4-Oxo-3-(3-phenyl-acryloylamino)-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-(6S)-carboxylicacid (96) A mixture of4-Oxo-3-(3-phenyl-acryloylamino)-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-(6S)-carboxylicacid ethyl ester (95, 3.1 g, 8.8 mmol) and aqueous 1N lithium hydroxide(8.8 mL, 8.8 mmol) in methanol (10 mL) was stirred 18 h at roomtemperature. The reaction was diluted with water and washed with ethylether (1×20 mL). The aqueous layer was acidified with conc. hydrochloricacid. The solid was collected by filtration and washed with water. Thesolid was dried in a vacuum oven at 50° C. for 18 h to give 2.2 g (75%)of the title compound as a tan solid: ¹ H NMR(CD₃ OD) δ2.4(m 1H), 2.7(m,1H), 3.1(m, 1H), 3.2(m, 1H), 5.15(dd, 1H), 7.0(d, 1H), 7.4(m, 3H),7.6(m, 2H), 7.65(d, 1H), 8.95(s, 1H)

4-Oxo-3-(3-phenyl-acryloylamino)-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-(6S)-carboxylicacid (2-benzyloxy-5-oxo-tetrahydro-furan-(3S)-yl)-amide (97) wasprepared from 96 by the method described in example 3 for compound H,step A to give 0.52 g (75%) of the title compound as a mixture ofdiastereomers: ¹ H NMR(CDCl₃) δ2.3-2.7(m, 3H), 2.9(dd, 1H), 3.05(m, 1H),3.3(m, 1H), 4.4-4.8(m, 2H), 4.9(2×d, 1H), 5.05(m, 1H), 5.55(2×s, 1H),6.6(2×d, 1H), 7.4(m, 6H), 7.55(m, 4H), 7.65(2×d, 1H), 8.0(m, 2H),9.2(s×2, 1H).

4-Oxo-(3S)-{[4-oxo-3-(3-phenyl-propionylamino)-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-(6S)-carbonyl]-amino}-butyricacid (98) was prepared by the procedure in example 3 for compound H,step D to give 0.13 g (45%) of the title compound: ¹ H NMR(CD₃ OD)δ2.35(m, 1H), 2.45-2.75(m, 3H), 2.8(t, 2H), 3.0(t, 2H), 3.1(m, 1H),3.25(m, 1H), 4.3(m, 1H), 6.65(dd, 1H), 5.15(m, 1H), 7.15(m, 1H), 7.3(m,4H), 8.8(a,1H). ##STR167##

3(S)-(Allyloxycarbonyl)-amino-4-[(2,6-dichlorophenyl)-oxazol-2-yl]-4(R,S)-hydroxy-butyricacid tert-butyl eater (99). A solution of 5-(2,6-Dichlorophenyl)oxazole(2.71 g, 12.7 mmol; prepared by a similar method described in Tet. Lett.23, p2369 (1972)) in tetrahydrofuran (65 mL) was cooled to -78° C. undera nitrogen atmosphere. To this solution was added n-butyl lithium (1.5 Msolution in hexanes, 8.5 mL, 13.3 mmol) and stirred at -78° C. for 30min. Magnesium bromide etherate (3.6 g, 13.9 mmol) was added and thesolution was allowed to warm to -45° C. for 15 min. The reaction wascooled to -78° C. and aldehyde 58 (3.26 g, 12.7 mmol; Graybill et al.,Int. J. Protein Res., 44, pp. 173-182 (1993)) in tetrahydrofuran (65 mL)was added dropwise. The reaction was stirred for 25 min., then allowedto warm to -40° C. and stirred for 3 h, and then at room temperature for1 h. The reaction was quenched with 5% NaHCO₃ (12 mL) and stirred for 3h. The tetrahydrofuran was removed in vacuo and the resulting residuewas extracted with dichloromethane. The organic layer was washed withsaturated sodium chloride solution and dried over magnesium sulfate,filtered, and concentrated to yield 6.14 g of the title compound.Purification gave 4.79 g (80%) of 99: ¹ H NMR (CDCl₃) δ1.45(s, 9H),2.7-2.5(m, 2H), 2.8(dd, 1H), 4.2, 4.4(2×d, 1H), 4.7-4.5(m, 3H),5.35-5.1(m, 2H), 5.6, 5.7(2×d, 1H), 6.0-5.8(m, 1H), 7.2(d, 1H), 7.3(m,1H), 7.4(m, 2H).

4-Oxo-3-(3-phenyl-propionylamino)-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-(6S)-carboxylic acid (100). A mixture of4-Oxo-3-(3-phenyl-acryloylamino)-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-(6S)-carboxylicacid (96; 2.1 g, 6.5 mmol) and 20% palladium hydroxide on carbon (0.5 g)in methanol (50 mL) was stirred under a hydrogen atmosphere for 4 h. Theresulting mixture was filtered and concentrated to yield 2.1 g (100%) ofthe title compound as a white solid: ¹ H NMR(CD₃ OD) δ2.35(m, 1H),2.65(m, 1H), 2.75(t, 2H), 3.0(t, 2H), 3.1(m, 1H), 3.15(m, 1H), 5.1(dd,1H), 7.15(m, 1H), 7.25(m, 4H), 8.75(s, 1H) ##STR168##

2,6-Dichloro-benzoic acid4-tert-butoxycarbonyl-2-oxo-{3S)-([4-oxo-3-(3-phenyl-propionylamino)-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-(6S)-carbonyl]-amino}-butylester (101a) was prepared by the procedure in example 5 for compound 56ato give 0.16 g (20%) of the title compound: ¹ H NMR(CD₃ OD) δ1.45(s,9H), 2.3(m, 1H), 2.6(m,1H), 2.7(m, 3H), 2.95(m, 3H), 4.8(m, 1H), 5.1(m,1H), 5.2(q, 2H), 7.1(m, 1H), 7.2(m, 4H), 7.4(m, 3H), 8.75(s, 1H).

4-(7-methoxy-benzoxazol-2-yl)-4-oxo-(3S)-{[4-oxo-3-(3-phenyl-propionylamino)-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-(6S)-carbonyl]-amino}-butricacid tert-butyl ester (101b).4-Hydroxy-4-(7-methoxy-benzoxazol-2-yl)-(3S)-{[4-oxo-3-(3-phenyl-propionylamino)-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-(6S)-carbonyl]-amino}-butyricacid tert-butyl ester was prepared from 100 and 66a by the procedure inexample 5 for compound 67a to give 0.95 g (quantitative) of the productas a mixture of diastereomers: ¹ H NMR(CD₃ OD) δ1.45(2×s, 9H), 2.2(2×m,1H), 2.35-3.0(m, 9H), 4.0(m, 3H), 4.75(m,1H), 4.85(m, 1H), 5.05(2×dd,1H), 7.1(2×dd, 1H), 7.15-7.3(m, 4H), 7.5(2×t, 1H), 7.8(2×d, 1H),8.55(2×dd, 1H), 8.7(2×s, 1H). The resulting product was converted to101b by the procedure in example 5 for compound 68a to give 0.36 g (50%)of the title compound: ¹ H NMR(CD₃ OD) δ1.4(s, 9H), 2.35(m, 1H), 2.55(m,1H), 2.75(t, 2H), 2.95(t, 2H), 3.00(m,1H), 3.1(dd, 2H), 3.15(m, 1H),5.15(dd, 1H), 5.65(t, 1H), 7.1(m, 2H), 7.2(m, 4H), 7.4(m, 2H), 8.7(s,1H)

4-[5-(2,6-Dichloro-phenyl)-oxazol-2-yl]-4-oxo-(3S)-{[4-oxo-3-(3-phenyl-propionylamino)-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-(6S)-carbonyl]-amino}-butyricacid tert-butyl ester (101c).4-[5-(2,6-Dichloro-phenyl)-oxazol-2-yl]-4-hydroxy-(3S)-{[4-oxo-3-(3-phenyl-propionylamino)-4,6,7,8-tetrahydro-pyrrolo[1,2-a)pyrimidine-(6S)-carbonyl]-amino}-butyricacid tert-butyl ester from 100 and 99 using the method described inexample 5, compound 67a to give 0.09 g (60%) of the product as a mixtureof diastereomers: ¹ H NMR(CD₃ OD) 51.45(2×s, 9H), 2.2(m, 1H), 2.5(m,2H), 2.7(2×dd, 1H), 2.75(t, 2H), 2.9-3.1(m, 4H), 4.7(m, 1H), S.1(m, 2H),7.1(m, 1H), 7.1-7.25(m, 4H), 7.4(t, 1H), 7.5(t, 1H), 8.55(d, 1H),8.75(s, 1H). The resulting product was converted to 101c by the methoddescribed in example 5, compound 68a to give 0.04 g (45%) of the titlecompound: ¹ H NMR(CD₃ OD) δ1.4(s, 9H), 2.3(m, 1H), 2.6(m, 1H), 2.75(t,2H), 2.95(t, 2H), 2.9-3.2(m, 4H), 5.2(dd, 1H), 5.55(t, 1H), 7.1(m, 1H),7.25(m, 4H), 7.55(m, 3H), 8.75(s, 1H).

2,6-Dichloro-benzoic acid4-carboxy-2-oxo-(3S)-{[4-oxo-3-(3-phenyl-propionylamino)-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-(6S)-carbonyl]-amino}-butyleater (102a) was prepared from 101a by the procedure in example 5 forcompound 57a to give 0.12 g (80%) of the title compound: ¹ H NMR(CD₃ OD)δ2.35(m, 1H), 2.65(m, 1H), 2.75(m, 2H), 2.85(dd, 1H), 2.95(m, 2H),3.0(dd, 1H), 3.15(m, 1H), 3.25(m, 1H), 4.55(dd, 1H), 5.15(m, 1H),5.25(q, 2H), 7.15(m, 1H), 7.25(m, 4H), 7.45(m, 1H), 8.8(s, 1H).

4-(7-methyoxy-benzoxazol-2-yl)-4-oxo-(3S)-{[4-oxo-3-(3-phenyl-propionylamino)-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-(6S)-carbonyl]-amino)-butricacid (102b) was prepared from 101b by the procedure described in example5 for compound 69a to give 0.12 g (35%) of the title compound: ¹ HNMR(DMSO-d₆) δ2.1(m, 1H), 2.55(m, 1H), 2.7-3.1(m, 8H), 4.05(s, 3H),5.1(dd, 1H), 5.55(t, 1H), 7.2(m, 1H), 7.25(m, 5H), 7.5(t, 1H), 7.55(d,1H), 8.7(s, 1H), 9.2(d, 1H), 9.4(s, 1H), 12.7(br, 1H).

4-[5-(2,6-Dichloro-phenyl)-oxazol-2-yl]-4-oxo-(3S)-{[4-oxo-3-(3-phenyl-propionylamino)-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidine-(6S)-carbonyl]-amino}-butyricacid (102c) was prepared from 101c as described in example 5 forcompound 69a to give 0.01 g (40%) of the title compound: ¹ H NMR(CD₃ OD)δ2.35(m, 1H), 2.6(m, 1H), 2.75(t, 2H), 2.95(t, 2H), 3.05(m, 1H), 3.15(m,3H), 5.15(dd, 1H), 5.55(t, 1H), 7.15(m, 1H), 7.2(m, 4H), 7.55(m, 3H),8.8(s, 1H) ##STR169##

(3-tert-Butoxycarbonylamino-2-oxo-2,3,4,5-tetrahydro-benzo[b][1,4]diazepin-1-yl)aceticacid methyl ester (103).

Step A. 2(S)-tert-Butoxycarbonylamino-3-(2-nitrophenyl-amino)-propionicacid. 2-tert-Butoxycarbonylamino-3-aminopropionic acid (10 g, 49 mmol),2-fluoronitrobenzene (5.7 ml, 54 mmol), and sodium bicarbonate (8.25 g,98 mmol) was taken into 130 ml of dimethylformamide and heated at 80° C.for 18 hours. The reaction was evaporated in vacuo to give a viscousorange residue that was dissolved in 300 ml of water and extracted withdiethyl ether (3×150 ml). The aqueous solution was acidified to pH 5with 10% sodium hydrogen sulfate and extracted with ethyl acetate (3×250ml). The combined extracts were dried over anhydrous sodium sulfate,filtered, and evaporated to give 12.64 g (83 %) of the title compound asan orange amorphous solid. ¹ H NMR (CD₃ OD) δ8.15-8.10 (1H,d), 7.54-7.48(1H,t), 7.13-7.08 (1H, d), 6.73-6.65 (1H, t), 4.45-4.35 (1H, m), 3.9-3.8(1H, dd), 3.65-3.55 (1H, dd), 1.45 (9H, s).

Step B. 2(S)-tert-Butoxycarbonylamino-3-(2-aminophenyl-amino)-propionicacid. A mixture of2-tert-Butoxycarbonylamino-3-(2-nitrophenylamino)propionic acid (12.65g, 40.5 mmol) and 0.5 g of 10% Pd/C in 100 ml of methanol under hydrogenat 1 atmosphere was stirred for 4 hrs. The solution was filtered throughCelite 545 and the filtrate evaporated in vacuo to afford 11.95 g of thetitle compound in quantitative yield as a dark brown solid that was usedwithout purification. ¹ H NMR (CD₃ OD) δ6.75-6.70 (3H,m), 6.65-6.58 (1H,m), 4.35-4.3 1H, m), 3.6-3.38 (2H, m), 1.45 (9H, s).

Step C.3(6)-tert-Butoxycarbonylamino-1,3,4,5-tetrahydro-benzo[b][1,4]diazepin-2-one.1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (8.54 g,44.5 mmol) was added to a cooled (0° C.) solution of2-tert-butoxycarbonylamino-3-(2-aminophenylamino)propionic acid (11.95g, 40.5 mmol) in 100 ml of dimethylformamide and stirred for 18 hours.The reaction was poured into 700 ml of ethyl acetate and washed fourtimes with 100 ml of water. The organic layer was dried over anhydroussodium sulfate, filtered, and evaporated to give a brown solid that waspurified by flash chromatography eluting with 3:7 ethyl acetate/hexaneto give 8 g (71%) of the title compound: ¹ H NMR (CDCl₃) δ7.78 (1H, s),7.02-6.95 (1H, m), 6.88-6.82 (1H, m), 6.82-6.78 (1H, m), 6.75-6.70 (1H,m), 5.8-5.7 (1H, d), 4.55-4.45 (1H, m), 3.95 (1H, s), 3.9-3.82 (1H, m),3.48-3.40 (1H,m), 1.45 (9H,s).

Step D.(3(S)-tert-Butoxycarbonylamino-2-oxo-2,3,4,5-tetrahydrobenzo[b][1,4]diazepin-1-yl)aceticacid methyl ester (103). A 1.0 M solution of lithiumbis(trimethylsilyl)amide (3.4 ml, 3.4 mmol) in THF was added dropwise toa -78° C. solution of3-tert-butoxycarbonylamino-1,3,4,5-tetrahydrobenzo[b][1,4]diazepin-2-one(0.94 g, 3.38 mmol) in 20 ml of anhydrous tetrahydrofuran and stirredfor 30 minutes. Methyl bromoacetate (o.44 ml, 4 mmol) was added dropwiseto the reaction mixture then warmed to room temperature. The reactionwas diluted with 100 ml of ethyl acetate and washed with 0.3 N potassiumhydrogen sulfate (50 ml), water (2×50 ml), and brine. The combinedorganics were dried over anhydrous sodium sulfate, filtered, andevaporated to afford a gum that was purified by flash chromatographyeluting with 3:7 EtOAc/Hex. to give 0.98 g (83%) of the title compoundas a white solid. ¹ H NMR (CDCl₃) δ7.15-7.07 (2H, m), 6.98-6.94 (1H, m),6.88-6.84 (1H, d), 5.62-5.55 (1H, d), 4.71-4.65 (1H, d), 4.65-4.6 (1H,m), 4.33-4.27 (1H, d), 3.96-3.90 (1H, m), 3.78 (3H, s), 3.44-3.37 (1H,m), 1.4 (9H, s). ##STR170##

[2-Oxo-3(S)-(3-phenylpropionylamino)-2,3,4,5-tetrahydro-benzo[b][1,4]diazepin-1-yl]aceticacid methyl ester (104a). Anhydrous hydrogen chloride was bubbled into asolution of(3(S)-tert-butoxycarbonylamino-2-oxo-2,3,4,5-tetrahydro-benzo[b][1,4]diazepin-1-yl)aceticacid methyl ester (103, 1 g, 2.86 mmol) in 25 ml of ethyl acetate for 2minutes then stirred for 1 hour at room temperature. The reaction wasevaporated to give2-oxo-3(S)-amino-2,3,4,5-tetrahydrobenzo(b][1,4]diazepin-1-yl aceticacid methyl ester hydrochloride as a white solid. The hydrochloride saltand hydrocinnamic acid (0.47 g, 3.15 mmol) was dissolved into 20 ml ofdimethylformamide and cooled to 0° C. Diisopropylethylamine (1 ml, 5.72mmol) was added to the solution followed by the addition ofN-hydroxybenzotriazole and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimidehydrochloride. After stirring for 18 hours at room temperature, themixture was diluted with 150 ml of ethyl acetate and washed with 10%sodium hydrogen sulfate, 10% sodium bicarbonate, and brine. The organiclayer was dried over anhydrous sodium sulfate, filtered, and evaporatedto a crude solid that was purified by flash chromatography eluting with7:3 ethyl acetate/dichloromethane to afford 600 mg (55%)of the titlecompound as a white solid. ¹ H NMR (CDCl₃) δ7.3-6.85 (9H,m), 6.55-6.0(1H, d), 4.88-4.82 (1H, m), 4.72-4.65 (1H, d), 4.28-4.22 (1H, m),3.95-3.9 (1H, m), 3.78 (3H, s), 3.65 (1H, br. s), 3.28-3.2 (1H, m),2.95-2.84 (2H, m), 2.55-2.4 (2H, m).

(3(S)-(3-Phenylpropionylamino)-2-oxo-2,3,4,5-tetra-hydrobenzo[b][1,4]diazepin-1-yl)aceticacid (105a).(3(S)-(3-Phenylpropionylamino)-2-oxo-2,3,4,5-tetrahydro-benzo[b][1,4]diazepin-1-yl)aceticacid methyl ester (104a) was dissolved in 90% methanol. Lithiumhydroxide hydrate was added to the reaction and the reaction was stirredat room temperature for 4 h. The reaction was evaporated in vacuo togive a white solid. This was dissolved in 20 ml of water and acidifiedto pH 5 and extracted with ethyl acetate to afford 304 mg (88%) of thetitle compound as a white solid. ¹ H NMR (CDCl₃) δ7.5-6.9 (11H, m),4.92-4.8 (1H, m), 4.7-4.58 (1H, d), 4.38-4.25 (1H, d), 3.88-3.78 (1H,m), 3.45-3.25 (1H, m), 3.05-2.85 (2H, m), 2.55-2.45 (2H, m)

4-Oxo-3(S)-{2-[2-oxo-3(S)-(3-phenylpropionylamino)-2,3,4,5-tetrahydro-benzo[b][1,4]diazepin-1-ylacetylamino}butyricacid (106a).N-[1-(2-Benzyloxy-5-oxotetrahydrofuran-3-ylcarbamoyl-methyl)-2-oxo-2,3,4,5-tetrahydro-1H-benzo[b][1,4]diazepin-3-yl]-3-phenylpropionamidewas prepared from 105a by the procedure in example 3, compound H (stepA)to afford 390 mg (93%) of the product as diastereomers. ¹ H NMR (CD₃ OD)δ7.58-7.22 (14H, m), 5.78-5.73 (0.5H, d), 5.64 (0.5H, s), 5.0-4.72 (4H,m), 4.54-4.42 (2H, m), 3.82-3.76 (0.5H, m), 3.68-3.62 (o.5H, m),3.28-3.21 (0.5H, m), 3.19-3.12 (0.5H, m), 3.07-2.98 (2H, m), 2.78-2.48(4H, m). The resulting product was converted to 106a by the methoddescribed in example 3, compound H (StepD) to afford the title compoundas a white solid (17%): ¹ H NMR (CD₃ OD) δ7.54-6.98 (9H, m), 5.58-5.44(1H, m), 4.8-4.2 (4H, m), 3.96-3.3 (2H, m), 3.30-3.05 (1H, m), 2.98-2.25(5H, m).

[2-Oxo-5-(3-phenylpropionyl)-3(S)-(3-phenylpropionylamino)-2,3,4,5-tetrahydrobenzo[b][1,4]diazepin-1-yl]aceticacid methyl ester (104b). Anhydrous hydrogen chloride was bubbled into asolution of(3(S)-tert-butoxycarbonylamino-2-oxo-2,3,4,5-tetrahydro-benzo[b][1,4]diazepin-1-yl)aceticacid methyl ester (103, 1 g, 2.86 mmol) in 25 ml of ethyl acetate for 2minutes then stirred for 1 hour at room temperature. The reaction wasevaporated to give2-oxo-3(S)-amino-2,3,4,5-tetrahydrobenzo[b][1,4]diazepin-1-yl aceticacid methyl ester hydrochloride as a white solid. The hydrochloride saltwas suspended into 20 ml of dichloromethane and cooled to 0° C.Triethylamine (1.6 ml, 11.5 mmol) was added to the suspension followedby the dropwise addition of dihydrocinnamoyl chloride (0.9 ml, 6 mmol).The mixture was warmed to room temperature and stirred for 18 hours. Themixture was diluted with 25 ml of dichloromethane and washed twice with50 ml of water and once with 50 ml of brine. The organic layer was driedover anhydrous sodium sulfate, filtered, and evaporated to give aviscous, yellow oil that was purified by flash chromatography elutingwith 1:1 ethyl acetate/dichloromethane to afford 1.35 g (92%) of thetitle product as a white solid. ¹ H NMR (CDCl₃) δ7.45-7.02 (14H, m),6.37-6.32 (1H, d), 4.78-4.72 (1H, m), 4.52-4.3 (3H, m), 3.82-3.77(1H,m), 3.74 (3H, s), 3.03-2.87 (4H, m), 2.58-2.45 (2H, m), 2.45-2.35(1H, m), 2.25-2.16 (1H, m).

[2-Oxo-5-(3-phenylpropionyl)-3-(3(S)-phenylpropionylamino)-2,3,4,5-tetrahydrobenzo[b][1,4]diazepin-1-yl]aceticacid (105b).[2-Oxo-5-(3-phenylpropionyl)-3-(3-phenylpropionylamino)-2,3,4,5-tetrahydrobenzo[b][1,4]diazepin-1-yl]aceticacid methyl ester (104b; 680 mg, 1.32 mmol) was hydrolyzed by theprocedure in example 105a to afford 645 mg (98%) of the title compoundas a white solid. ¹ H NMR (CDCl₃) δ7.58 (1H, br. s), 7.5-7.42 (1H, m),7.35-6.95 (14H, m), 4.95-4.88 (1H, m), 4.64-4.55 (1H, d), 4.54-4.45 (1H,t), 4.15-4.05 (1H, d), 3.75 (1H, m), 3.05-2.75 (4H, m), 2.58-2.45 (2H,m), 2.45-2.28 (1H, m), 2.25-2.14 (1H, m).

2-Oxo-3(S)-{2-[2-oxo-5-(3-phenylpropionyl)-3(S)-(3-phenyl-propionyl-amino)-2,3,4,5-tetrahydrobenzo[b][1,4]diazepin-1-yl]acetylamino}butyricacid (106b).[2-Oxo-5-(3-phenylpropionyl)-3-(3-phenylpropionylamino)-2,3,4,5-tetrahydrobenzob][1,4]diazepin-1-yl)acetic acid and 3-amino-4-oxobutyric acidtert-butylester semicarbazone were coupled by the procedure in example3, compound K (step A) to give 350 mg (85%) of a white solid. ¹ H NMR(CDCl₃) δ9.05 (1H, br. s), 7.58-7.55 (1H,d), 7.5-7.35 (1H, m), 7.35-6.95(14H, m), 6.75-6.72 (1H, d), 6.25 (1H, br. s), 5.25 (1H, br. s),4.95-4.88 (1H, m), 4.8-4.72 (1H, m), 4.55-4.4 (2H, m), 3.92-3.88 (1H,d), 3.73-3.68 (1H, m), 2.95-2.8 (4H, m), 2.8-2.72 (1H, m), 2.62-2.55(1H, m), 2.55-2.45 (2H, m), 2.4-2.32 (1H, m), 2.2-2.12 (1H, m), 1.45(9H, s).

4-Oxo-3-{2-[2-oxo-5-(3-phenylpropionyl)-3-(3-phenyl-propionyl-amino)-2,3,4,5-tetrahydrobenzo[b][1,4]diazepin-1-yl]-acetyl-amino}butyricacid tert-butyl ester semicarbazone was deprotected as described inexample 3, compound K (step C) to give 118 mg (47%) of the titlecompound as a white solid. ¹ H NMR (CD₃ OD) 87.48-6.95 (14H, m),4.65-4.15 (6H, m), 3.5-3.4 (1H, mi, 2.85-2.72 (4H, m), 2.65-2.5 (1H, m),2.5-2.34 (3H, m), 2.34-2.15 (2H, m).

[5-Benzyl-2-oxo-3(S)-(3-phenylpropionylamino)-2,3,4,5-tetrahydro-benzo[b][l,4]diazepin-1-yl]aceticacid methyl ester (104c).[2-Oxo-3-(3-phenylpropionylamino)-2,3,4,5-tetrahydrobenzo-[b][1,4]diazepin-1-yl]aceticacid methyl ester (104a; 500 mg, 1.31 mmol), calcium carbonate (155 mg,1.58 mmol), and benzyl bromide (170 μl, 1.44 mmol) were taken into 10 mlof dimethylformamide and heated to 80° C. for 8 hours. The mixture wasdiluted with 150 ml of ethyl acetate and washed 4 times with 50 ml ofwater. The organic layer was dried over anhydrous sodium sulfate,filtered, and evaporated to give a viscous, yellow oil that was purifiedby flash chromatography eluting with dichloromethane/ethyl acetate (8:2)to give 460 mg (75%) of the title compound as a white solid. ¹ H NMR(CDCl₃) δ7.34-7.05 (14H, m), 6.32-6.28 (1H, d), 4.84-4.76 (1H, d),4.76-4.70 (1H, m), 4.43-4.37 (1H, d), 4.26-4.18 (1H, d), 4.06-4.00 (1H,d), 3.79 (3H, s), 3.45-3.37 (1H, m), 3.02-2.95 (1H, m), 2.90-2.82 (2H,m), 2.5-2.34 (2H, m).

[5-Benzyl-2-oxo-3(S)-(3-phenylpropionylamino)-2,3,4,5-tetrahydro-benzo[b][1,4]diazepin-1-yl]aceticacid (105c) was prepared by the hydrolysis of the ester (102c) by theprocedure reported in example 105a to give 450 mg (98%) of the titlecompound as a white solid: ¹ H NMR (CD₃ OD) 37.5-7.05 (14H, m), 6.4 (1H,br. s), 4.85-4.55 (2H,m), 4.5-4.21 (2H, m), 4.12-3.92 (1H, d), 3.45-3.3(1H, m), 3.1-2.8 (3H, m), 2.55-2.28 (3H, m).

3(S)-{2-[5-Benzyl-2-oxo-3-(3(S)-phenylpropionylamino)-2,3,4,5-tetrahydrobenzo[b][1,4]diazepin-1-yl]-acetylamino}-4-oxobutyricacid (106c).[5-Benzyl-2-oxo-3(S)-(3-phenylpropionylamino)-2,3,4,5-tetrahydrobenzo[b[1,4]diazepin-1-yl]aceticacid and 3(S)-amino-4-oxobutyric acid tert-butylester semicarbazone werecoupled by the procedure in example 3, compound K (step A) and to afford260 mg (85%) of a white solid: ¹ H NMR (CD₃ OD) δ7.35-7.0 (15H, m),4.94-4.88 (1H, m), 4.68-4.58 (1H, d), 4.57-4.52 (1H, m), 4.41-4.34 (1H,d), 4.3-4.23 (1H, d), 4.1-4.04 (1H, d), 3.18-3.11 (1H, m), 3.09-2.98(1H, m), 2.78-2.72 (2H, t), 2.65-2.57 (1H, m), 2.42-2.33 (3H, m).3(S)-{2-[5-Benzyl-2-oxo-3(S)-(3-phenylpropionylamino)-2,3,4,5-tetrahydrobenzo[b][1,4]diazepin-1-yl]-acetylamino}-4-oxobutyricacid tert-butyl ester semicarbazone was deprotected as described inexample 3, compound K (step C) to give 168 mg (81%) of the titlecompound as a white solid. ¹ H NMR (CD₃ OD) δ7.37-7.0 (14H, m),4.75-4.62 (1H, m), 4.6-4.45 (2H, m), 4.4-4.21 (2H, m), 4.15-3.95 (2H,m), 3.15-3.0 (2H, m), 2.82-2.67 (2H, m), 2.65-2.52 (1H, m), 2.5-2.32(3H, m). ##STR171##

2,6-Dichlorobenzoic acid4-tert-butoxycarbonyl-2-oxo-3(S)-{2-[2-oxo-5-(3-phenylpropionyl)-3(S)-(3-phenylpropionylamino)-2,3,4,5-tetrahydro-benzo[b][1,4]diazepin-1-yl]acetyl-amino}butylester (107a). The resulting semicarbazone was prepared by the couplingof compound 105b and t-butyl3-(allyloxycarbonylamino)-4-oxo-5-(2,6-dichorobenzoyl-oxy)pentanoate (WO93 16710) as described in compound 56a to give 256 mg (58%) of the titlecompound as a white solid. ¹ H NMR (CDCl₃) δ7.45-7.04 (17H, m),6.45-6.34 (2H, m), 5.28-5.21 (1H, m), 5.1-5.0 (1H, m), 4.95-4.90 (1H,m), 4.75-4.70 (1H, m), 4.55-4.44 (1H, mn), 4.32-4.22 (1H, dd), 3.99-3.85(1H, dd), 3.85-3.76 (1H, m), 3.06-2.83 (5H, m), 2.83-2.74 (1H, m),2.6-2.44 (2H, m), 2.43-2.33 (1H, m), 2.24-2.15 (1H, m), 1.45 (9H, s).

2,6-Dichlorobenzoic acid4-carboxy-2-oxa-3(S)-{2-[2-oxo-5-(3-phenylpropionyl)-3(S)-(3-phenylpropionylamino)-2,3,4,5-tetrahydrobenzo[b][1,4]diazepin-1-yl]-acetylamino}butyl eater (108a)was prepared from 107a by the method described for compound 57a whichafforded 156 mg (68%) of the title compound as a white solid. ¹ H NMR(CD₃ OD) δ7.5-6.9 (17H, m), 5.16-5.02 (1H, dd), 4.88-4.71 (2H, m),4.62-4.44 (2H, m), 4.42-4.28 (2H, m), 4.27-4.18 (1H, m), 3.47-3.41 (1H,m), 2.90-2.60 (5H, m), 2.46-2.4 (2H, m), 2.39-2.18 (2H, m).

4-(7-Methoxybenzoxazol-2-yl)-4-oxo-3(S)-{2-[2-oxo-5-(3-phenylpropionyl)-3(S)-(3-phenylpropionylamino)-2,3,4,5-tetrahydrobenzo[b][1,4]diazepin-1-yl]acetylamino}butyric acid tert-butyl enter (107b). 4(R,S)-Hydroxy-4-(7-methoxybenzoxazol-2-yl) -3(S)-{2-[2-oxo-5-(3-phenylpropionyl)-3(S)-(3-phenylpropionylamino)-2,3,4,5-tetrahydro[b][1,4)diazepin-1-yl-acetylamino}butyricacid tert-butyl ester was prepared from 105b and 66a by the methoddescribed in example 5, compound 67 to give 56% of a white solid: ¹ HNMR (CDCl₃) 57.72-6.78 (19H, m), 6.37-6.28 (1H, m), 5.17-5.08 (0.5H, m),4.92-4.82 (0.5H, m), 4.81-4.6 (1H, m), 4.6-4.35 ((3H,m), 4.05-3.9 (1H,m), 3.95 (3H, s), 3.82-3.7 (1H, m), 2.96-2.05 (10H, m), 1.45 (4.5H, s),1.38 (4.5H, s). The resulting product was converted to 107b by themethod described in example 5, compound 68a to give the title compound(56%) as a white solid. ¹ H NMR (CD₃ OD) δ7.62-6.8 (17H, m), 5.64-5.58(0.5H, t), 5.52-5.46 (0.5H, t), 4.62-4.47 (2H, m), 4.40-4.32 (1H, m),3.9 (1.5H, s), 3.88 (1.5H, s), 3.43-3.37 (1H, m), 3.0-2.92 (1H, m),2.90-2.62 (6H, m), 2.5-2.4 (2H, m), 2.28-2.15 (2H, m), 1.32 (4.5H, s),1.25 (4.5H, s).

4-(7-Methoxybenzoxazol-2-yl)-4-oxo-3(S)-{2-[2-oxo-5-(3-phenylpropionyl)-3(S)-(3-phenylpropionylamino)-2,3,4,5-tetrahydrobenzo[b][1,4]diazepin-1-yl]-acetylamino}butyricacid (108b) was prepared by the method described in example 5, compound69a to give the title compound (50%) as a white solid. ¹ H NMR (CD₃ OD)δ7.41-6.88 (17H, m), 5.6-5.55 (0.5H, t), 5.48-5.43 (0.5H, t), 4.64-4.45(2H, m), 4.45-4.30 (1H, m), 3.93 (1.5H, s), 3.90 (1.5H, s), 3.47-3.34(1H, m), 3.10-2.85 (2H, m), 2.84-2.63 (5H, m), 2.6-2.4 (2H, m), 2.3-2.1(2H, m).

4-[5-(2,6-Dichlorophenyl)oxazol-2-yl]-4-oxo-3(S)-{2-[2-oxo-5-(3-phenylpropionyl)-3(S)-(3-phenylpropionylamino)-2,3,4,5-tetrahydrobenzo[b][1,4]diazepin-1-yl]-acetylamino}butyricacid tert-butyl ester (107c).4-[5-(2,6-Dichlorophenyl)oxazol-2-yl]-4(R,S)-hydroxy-3(S)-{2-[2-oxo-5-(3-phenylpropionyl)-3(S)-(3-phenylpropionylamino)-2,3,4,5-tetrahydrobenzo[b](1,4]diazepin-1-yl]-acetylamino}butyricacid tert-butyl ester was prepared from 106c and 99 by a similar methodas described for compound 67a in example 5 to give 72% of a white solid.¹ H NMR (CDCl₃) δ7.71-7.64 (1H, m), 7.58-7.42 (2H, m), 7.42-6.92 (15H,m), 6.5-6.37 (2H, m), 5.15-5.04 (1H, m), 4.88-4.68 (2H, m), 4.57-4.37(2H, m), 4.28-4.13 (1H, m), 3.87-3.64 (2H, m), 3.04-2.80 (4H, m),2.76-2.68 (1H, m), 2.67-2.42 (3H, m), 2.41-2.31 (1H, m), 2.22-2.12 (1H,m), 1.45 (9H, s). The resulting product was converted to 107c by asimilar method as described for compound 68a in example 5 to give thetitle compound in quantitative yield as a white solid. ¹ H NMR (CDCl₃)δ7.47-6.98 (18H, m), 6.52-6.42 (1H, d), 5.6-5.52 (1H, m), 4.78-4.71 (1H,m), 4.52-4.40 (2H, m), 4.03-3.94 (0.67H, m), 3.94-3.85 (0.33H, m),3.85-3.75 (1H, m), 3.45-3.33 (1H, m), 3.08-2.98 (1H, m), 2.97-2.84 (4H,m), 2.55-2.43 (2H, m), 2.43-2.32 (1H, m), 2.23-2.13 (1H, m), 1.35 (9H,s).

4-[5-(2,6-Dichlorophenyl)oxazol-2-yl]-4-oxo-3(S)-{2-[2-oxo-5-(3-phenylpropionyl)-3(S)-(3-phenylpropionylamino)-2,3,4,5-tetrahydrobenzo[b][1,4]diazepin-1-yl]-acetylamino}butyricacid (108c) was prepared from 107c by a similar method as described forcompound 69a in example 5 to give 72% the title compound as a whitesolid. ¹ H NMR (CD₃ OD) δ7.58-7.0 (18H, m), 5.62-5.53 (0.67H, m),5.52-5.47 (0.33H, m), 4.68 (3H, m), 3.54-3.42 (1H, m), 3.1-2.92 (2H, m),2.88-2.68 (5H, m), 2.63-2.45 (2H, m) 2.40-2.22 (2H, m). ##STR172##

3(S)-{2(R,S)-[4-Benzyl-7-oxo-6(S)-(N-benzyloxycarbonylamino)-[1,4]diazepan-1-yl]-propionylamino}-4-oxo-butyricacid trifluoroacetic acid salt (114a):

Step A. To a solution oftert-butyl-2-N-benzyloxycarbonyl-3-N-benzyl-(S)-2,3-diaminopropionate(110; 0.85 g, 2.2 mmol),3-(N-tert-butoxycarbonyl)amino-2-methyl-5-oxo-pentanoic acid methylester (109a; 0.65 g, 2.7 mmol), acetic acid (0.1 mL, 1.8 mmol), sodiumacetate (0.36 g, 2 mmol) and 4 Å molecular sieves (1 g) in methanol (45mL), was added sodium cyanoborohydride (0.33 g, 5.3 mmol). The mixturewas stirred overnight at 25° C. then filtered through Celite andconcentrated under reduced pressure. The residue was dissolved in 1 NNaOH and extracted with ethyl acetate (3×40 mL). The organic layer wasdried (MgSO₄), filtered and evaporated to give an oil. Chromatography(silica-gel, 4:1 hexane: ethyl acetate as eluent) gave 0.92 g (68%yield) of 111a as an oil.

Step B. The above material was dissolved in dichloromethane (3 mL)cooled to 0° C. and treated with a 25% solution of trifluoroacetic acidin dichloromethane (20 mL) then allowed to warm to 25° C. and stir untilthe reaction was judged complete by TLC (4:1 hexane:ethyl acetate). Thesolvent was removed under reduced pressure and the residue dried undervacuum then dissolved in dichloromethane (40 mL) and treated with4-methylmorpholine (1 mL, 9 mmol), HOBT (0.2 g, 1.5 mmol) and EDC (0.61g, 3.2 mmol). The resulting mixture was stirred overnight at 25° C. thendiluted with dichloromethane and washed with water. The organic layerwas dried (MgSO₄), filtered and evaporated to give an oil.Chromatography (silica-gel, 3:2 hexane: ethyl acetate) gave 0.49 g (74%yield) of 112a as a viscous oil.

Step C. A solution of2(R,S)-[4-benzyl-7-oxo-6(S)-(N-benzyloxycarbonylamino)-[1,4]diazepan-1-yl]-propionicacid methyl ester (112a; 0.15 g, 0.32 mmol) was dissolved in methanoland treated with 1 M LiOH (0.32 mL) and stirred 5.5 hours at 25° C. thenevaporated to dryness. The residue was azeotroped with-ethanol (2×10mL), acetonitrile (2×10 mL), benzene (2×10 mL) then dried under vacuum.The resulting residue was converted to 114a by a method similar to thatdescribed in example 3, compound K (steps A, B, and C) and purified byreverse phase (C18 column) HPLC using 0.1%TFA:water/0.1%TFA:acetonitrileas eluent. to give 17 mg (10% yield) of a viscous oil: ¹ H NMR (500 MHz,CD₃ OD) δ1.15 (m, 3H), 2.30-2.70 (m, 6H), 2.72-2.95 (bm, 6H), 3.30-3.80(m, 4H), 4.10 (m, 1H), 4.40 (m, 4H), 4.95 (m, 1H) 6.95-7.10 (bs, 5H),and 7.12-7.20 ppm (bs, 5H).

3(S)-{2-[4-Benzyl-7-oxo-6(S)-(N-benzyloxycarbonylamino)-[1,4]diazepan-1-yl]-acetylamino}-4-oxo-butyricacid trifluoroacetic acid salt (114b) was prepared from 109b by asimilar method described for the synthesis of 114a to give 85 mg ofviscous oil: ¹ H NMR (500 MHz, CD₃ OD) δ1.20 (d, J=7 Hz, 3H), 2.28 (m,2H), 2.60 (m, 2H), 3.18 (bs, 6H), 3.35-3.45 (m, 2H), 3.60-3.95 (m, 2H),4.15 (m, 1H), 4.32 (m, 1H), 4.42 (m, 1H), 5.00 (bm, 2H), 7.20 (bs, 5H),and 7.40 ppm (bs, 5H); ¹⁹ F NMR (470 MHz, CD₃ OD) δ-10.72 ppm (s, 3F).

4-Oxo-3(S)-(2(R,S)-[7-oxo-4-(3-phenyl-propionyl)-6(S)-(3-phenyl-propionylamino)-[1,4]diazepan-1-yl]-propionylamino}-butyricacid (115): Step D. A suspension of2(R,S)-[4-benzyl-7-oxo-6(S)-(N-benzyloxycarbonylamino)-[1,4]diazepan-1-yl]-propionicacid methyl ester (112b; 0.22 g, 0.49 mmol) and 20% Pd(OH)₂ on carbon(50 mg) in ethanol was stirred under hydrogen atmosphere for 7 hours.The solvent was evporated under reduced pressure and the residuedissolved in dichloromethane (20 mL) then treated with triethylamine (1mL) and dihydrocinnamoyl chloride (170 mg, 1 mmol). The resultingmixture was allowed to stir overnight then diluted with ethyl acetateand washed with 1 N NaOH. The organic layer was dried (MgSO₄), filteredand evaporated to give an oil. Chromatography (silica-gel, 4:1 hexane:ethyl acetate) gave 0.175 g (75% yield) of 113 as an oil.

Step C. A 0.15 g sample of 113 (0.32 mmol) was dissolved in methanol,treated with 1 M LiOH (0.32 mL), stirred at 40° C. overnight thenevaporated to dryness. The residue was azeotroped with ethanol (2×10mL), acetonitrile (2×10 mL), benzene (2×10 mL) then dried under vacuum.The resulting residue was converted to 115 by a method similar to thatdescribed in example 3, compound K (steps A, B, and C). ##STR173##

3-{2-[2,4-Dibenzyl-3,7-dioxo-6-(N-benzyloxycarbonylamino)-[1,4]diazepan-1-yl]-acetylamino}-4-oxo-butyricacid (121): Step E. A solution oftert-butyl-2-N-carbobenzoxy-3-N-benzyl-(S)-2,3-diaminopropionate (110;1.77 g, 4.6 mmol), N-allyl-N-tert-butoxycarbonyl-(S)-phenylalanine (116;1.04 g, 4.8 mmol), HOBT (0.74 g, 5.5 mmol) and EDC (1.33 g, 6.9 mmol) indichloromethane (50 mL) was allowed to stirr at 25° C. for 16 h thendiluted with dichloromethane (100 mL) and washed with water. The organiclayer was dried (MgSO₄), filtered and evaporated to give an oil.Chromatography (silica-gel, 85:15 hexane:ethyl acetate) gave 1.34 g (43%yield) of 117 as a colorless viscous oil.

Step F. A 1.34 g sample of 117 was dissolved in dichloromethane (3 mL)and treated with a 50% solution of trifluoroacetic acid indichloromethane (20 mL). After 1.5 h, the solvent was removed underreduced pressure and the residue dried under vacuum then dissolved indichloromethane (50 mL) and combined with 4-methylmorpholine (0.2 mL, 2mmol), HOBT (0.27 g, 2 mmol) and EDC (0.8 g, 4 mmol). The mixture wasstirred overnight at 25° C. then diluted with dichloromethane and washedwith water. The organic layer was dried (MgSO₄), filtered and evaporatedto give an oil. Chromatography (silica-gel, 7:3 hexane: ethyl acetate)gave 0.8 g (80% yield) of 118 as a viscous oil.

Step G. A 0.8 g sample of 118 was dissolved in methanol (40 mL), cooledto -78° C. and saturated with ozone until the solution was blue incolor. The excess ozone was removed by purging with argon thendimethylsulfide (5 mL) was added and the mixture allowed to warm to 25°C. and stir 3 h. Solvent removal and chromatography (silica-gel, 1:1hexane:ethyl acetate) gave 0.74 g (74% yield) of 119 as a white solid.

Step H. A 0.2 g sample (0.4 mmol) of 119 was dissolved in acetone (25mL), cooled to 0° C. and treated dropwise with a solution of Jonesreagent until the orange color persisted. 2-Propanol (5 mL) was thenadded to the mixture and the resulting soltuion filtered through Celiteand washed with acetone. Solvent removal gave a green-white solid thatwas dried under vacuum to give 120. The resulting residue was convertedto 121 by a method similar to that described in example 3, compound K(steps A, B, and C). Chromatography (SiO₂, 95:4.5:0.5 dicholormethane:methanol: acetic acid eluent) gave 85 mg (53% yield) of cream coloredsolid which was identified as3-{2-[2,4-dibenzyl-3,7-dioxo-6-(N-benzyloxycarbonylamino)-[1,4]diazepan-1-yl-acetylamino}-4-oxo-butyricacid (121) on the basis of the following spectral data: ¹ H NMR (500MHz, CD₃ OD) δ2.38 (m, 1H), 2.45 (m, 1H), 3.21 (bs, 2H), 3.32-3.39 (bm,6H), 3.85 (m, 1H), 4.05 (m, 1H), 4.21 (bm, 1H), 4.31 (bs, 1H), 4.45 (dm,J=11 Hz, 1H), 4.95 (bs, 4H), 7.20 (bs, 5H), and 7.33-7.45 ppm (m, 5H);¹⁹ F NMR (470 MHz, CD₃ OD) d-10.62 ppm (s, 3 F). ##STR174##

t-Butyl (3S)N-(allyloxycarbonyl)-3-amino-5-(2-chlorophenylmethylthio)-4-oxo-pentanoate(123). Potassium fluoride (273 mg, 4.70 mmol) and then2-chlorophenylmethyl thiol (373 mg, 2.35 mmol) were added to a stirredsolution of (3S) t-butylN-(allyloxycarbonyl)-3-amino-5-bromo-4-oxo-pentanoate (122; 749 mg, 2.14mmol; WO 93 16710) in dimethylformamide (20 ml). The mixture was stirredfor 3.5 h, quenched with water (50 ml) and extracted with ethyl acetate(2×50 ml). The combined organic extracts were washed with water (4×50ml) then brine (50 ml). They were dried (MgSO₄) and concentrated toafford an oil which was purified by flash chromatography (10-35% ethylacetate/hexane) to afford 832 mg (91%) of a colourless solid: mp. 45-6°C.; [α]_(D) ²⁰ -19.0° (c 1.0, CH₂ Cl₂); IR (film) 3340, 2980, 2935,1725, 1712, 1511, 1503, 1474, 1446, 1421, 1393, 1368, 1281, 1244, 1157,1052, 1040, 995, 764, 739; ¹ H NMR (CDCl₃) δ7.36 (2H, m), 7.21 (2H, m),5.91 (2H, m), 5.27 (2H, m), 4.76 (1H, m), 4.59 (2H, d), 3.78 (2H, s),3.36 (2H, m), 2.91 (1H, dd), 2.74 (1H, dd), 1.43 (9H, s). Anal. Calcdfor C₂₀ H₂₆ ClNO₅ S: C, 56.13; H, 6.12; N, 3.27; S, 7.49. Found: C,56.08; H, 6.11; N, 3.26; S, 7.54. MS (C.I.) 430/28 (M⁺ +1, 3%), 374/2(100).

t-Butyl (3S)3(2(6-benzyl-1,2-dihydro-2-oxo-3(3-phenylpropionylamino)-1-pyridyl)acetylamino-5-(2-chlorophenylmethylthio)-4-oxopentanoate(124a). 6-Benzyl-1,2-dihydro-2-oxo-3-(3-phenylpropionylamino)-pyridylacetic acid (52b; 300 mg, 0.76 mmol) in THF (7 ml) was stirred with1-hydroxybenzotriazole (205 mg, 1.52 mmol) and1-(3-dimethylaminopropy-3-ethylcarbodiimide hydrochloride). After 3 min,water (12 drops) was added and the mixture stirred 10 min then treatedwith t-butyl (3S)N-(allyloxycarbonyl)-3-amino-S-(2-chlorophenylmethylthio)-4-oxopentanoate(123) (325 mg, 0.76 mmol), bis (triphenylphosphine) palladium IIchloride (20 mg) and tributyltin hydride (0.6 ml, 2.28 mmol). Themixture was stirred for 5 h at room temperature, poured into ethylacetate and washed with aqueous 1 M HCl (×2), aqueous sodiumbicarbonate, brine, dried (MgSO₄) and concentrated. The residue wastriturated with pentane and the supernatant discarded. Chromatography(silica gel, 50% ethyl acetate/hexane) afforded a colourless foam (439mg, 81%): [α]_(D) ²¹ -18.3° (c 0.5, CH₂ Cl₂); IR (KBr) 3356, 3311, 1722,1689, 1646, 1599, 1567, 1513, 1367, 1154; ¹ H NMR (CDCl₃) δ8.39 (1H, d),8.23 (1H, s), 7.24 (14H, m), 6.16 (1H, d), 4.95 (1H, m), 4.63 (2H, m),4.02 (2H, s), 3.74 (2H, s), 3.27 (2H, s), 2.85 (6H, m), 1.40 (9H, s).Anal. Calcd for C₃₉ H₄₂ ClN₃ O₆ S: C, 65.39; H, 5.91; N, 5.87. Found: C,65.51; H, 5.99; N,5.77.

t-Butyl[3S(1S,9S)]-3-(6,10-dioxo-1,2,3,4,7,8,9,10-octahydro)-9-(3-phenylpropionylamino)-6H-pyridazine[1,2-a][1,2]diazepine-1-carboxamido-5-(2-chlorophonylmethylthio)-4-oxopentanoate(124b) was prepared by a similar method as 124a from the thioether 123and3S(1S,9S)-3-(6,10-dioxo-1,2,3,4,7,8,9,10-octahydro)-9-(3-phenylpropionylamino)-6H-pyridazino[1,2-a][1,2]diazepine-1-carboxylicacid (45a) to afford 452 mg (50%) of colourless foam: mp 55-7° C.;[α]_(D) ²² -94.0° (c 0.12, CH₂ Cl₂); IR (KBr) 3288, 2934, 1741, 1722,1686, 1666, 1644, 1523, 1433, 1260, 1225, 1146, 757; ¹ H NMR (CDCl₃)δ7.35 (3H, m), 7.20 (7H, m), 6.46 (1H, d), 5.21 (1H, m), 4.97 (2H, m),4.56 (1H, m), 3.75 (2H, s), 3.25 (3H, m), 2.93 (5H, m), 2.71 (1H, dd),2.55 (2H, m), 2.30 (1H, m), 1.92 (3H, m), 1.66 (2H, m), 1.42 (9H, s).Anal. Calcd for C₃₅ H₄₃ ClN₄ O₇ S. 0.25H₂ O: C, 59.73; H, 6.23; Cl,5.04; N, 7.96; S, 4.56. Found: C, 59.73; H, 6.19; Cl, 5.10; N, 7.79; S,4.58. MS (-FAB) 697 (M-1, 100).

(3S)3(2(6-Benzyl-1,2-dihydro-2-oxo-3-(3-phenylpropionylamino)-1-pyridyl)acetylamino-5-(2-chlorphenylmethylthio)-4-oxopentanoicacid (125a).t-Butyl-3(2(6-benzyl-1,2-dihydro-2-oxo-3-(3-phenylpropionylamino)-1-pyridyl)acetyl-amino-5-(2-chlorophenylmethylthio)-4-oxopentanoate(124a) (400 mg, 0.56 mmol) in dichloromethane (3 ml) at 0° C. wastreated with trifluoroacetic acid (3 ml) and stirred at 0° C. for 1 hand room temperature for 0.5 h. The solution was concentrated thenredissolved in dichloromethane and reconcentrated. This procedure wasrepeated three times. The residue was stirred in ether for 1 hr andfiltered to yield a colourless solid (364 mg, 99%): mp. 165-7° C.;[α]_(D) ²² -27.7° (c 0.2, CH₂ Cl₂); IR (KBr) 3289, 1712, 1682, 1657,1645, 1593, 1562, 1527, 1497, 1416, 1203, 1182; ¹ H NMR (CDCl₃) d 8.47(1H, d), 8.21 (1H, s), 7.70 (1H, d), 7.22 (14H, m), 6.24 (1H, d), 5.03(1H, m), 4.65 (2H, m), 4.06 (2H, s), 3.69 (2H, m), 3.23 (2H, m), 2.88(6H, m).

[3S(1S,9S)]-3-(6,10-dioxo-1,2,3,4,7,8,9,10-octahydro)-9-(3-phenylpropionyl-amino)-6H-pyridazine[1,2-a][1,2]diazepine-1-carboxamido-5-(2-chlorophenyl-methylthio)-4-oxopentanoicacid (125b), was prepared by a similar method as 125a from the t-butylester 124b to afford 362 mg (93%) of colourless powder: mp 76-80° C.;[α]_(D) ²¹ -134° (c 0.10, MeOH); IR (KBr) 3309, 2935, 1725, 1658, 1528,1445, 1417, 1277, 1219, 1175; ¹ H NMR (D₆ -DMSO) δ8.80 (1H, d), 8.19(1H, d), 7.31 (9H, m), 5.09 (1H, m), 4.74 (1H, m), 4.63 (1H, m), 4.35(1H, m), 3.76 (2H, m), 3.28 (3H, m), 2.80 (5H, m), 2.52 (4H, m), 2.16(2H, m), 1.90 (3H, m). Anal. Calcd for C₃₁ H₃₅ Cl₂ N₄ O₇ S. 0.25H₂ O: C,57.49; H, 5.53; N, 8.65; S, 4.95. Found: C, 57.35; H, 5.43; N. 8.45; S,4.88. MS (-FAB) 641 (M-1, 100).

The data of the examples above demonstrate that compounds according tothis invention display inhibitory activity towards IL-1β ConvertingEnzyme.

Insofar as the compounds of this invention are able to inhibit ICE invitro and furthermore, may be delivered orally to mammals, they are ofevident clinical utility for the treatment of IL-1 mediated diseases.These tests are predictive of the compounds ability to inhibit ICE invivo.

While we have described a number of embodiments of this invention, it isapparent that our basic constructions may be altered to provide otherembodiments which utilize the products and processes of this invention.Therefore, it will be appreciated that the scope of this invention is tobe defined by the appended claims, rather than by the specificembodiments which have been presented by way of example.

    __________________________________________________________________________    #             SEQUENCE LISTING                                                - (1) GENERAL INFORMATION:                                                    -    (iii) NUMBER OF SEQUENCES: 2                                             - (2) INFORMATION FOR SEQ ID NO:1:                                            -      (i) SEQUENCE CHARACTERISTICS:                                          #acids    (A) LENGTH: 4 amino                                                           (B) TYPE: amino acid                                                          (C) STRANDEDNESS: single                                                      (D) TOPOLOGY: linear                                                -     (ii) MOLECULE TYPE: peptide                                             -    (iii) HYPOTHETICAL: NO                                                   -     (iv) ANTI-SENSE: NO                                                     -     (ix) FEATURE:                                                                     (A) NAME/KEY: Modified-sit - #e                                               (B) LOCATION: 1                                                     #/product= "OTHER"R INFORMATION:                                              #"tyrosine is succinylated"                                                   -     (ix) FEATURE:                                                                     (A) NAME/KEY: Modified-sit - #e                                               (B) LOCATION: 4                                                     #/product= "OTHER"R INFORMATION:                                              #"aspartic acid residue is derivatized with                                                  p-nitroanili - #de"                                            -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:                                 - Tyr Val Ala Asp                                                             - (2) INFORMATION FOR SEQ ID NO:2:                                            -      (i) SEQUENCE CHARACTERISTICS:                                          #acids    (A) LENGTH: 4 amino                                                           (B) TYPE: amino acid                                                          (C) STRANDEDNESS: single                                                      (D) TOPOLOGY: linear                                                -     (ii) MOLECULE TYPE: peptide                                             -    (iii) HYPOTHETICAL: NO                                                   -     (iv) ANTI-SENSE: NO                                                     -     (ix) FEATURE:                                                                     (A) NAME/KEY: Modified-sit - #e                                               (B) LOCATION: 1                                                     #/product= "OTHER"R INFORMATION:                                              #"tyrosine is acetylated"                                                     -     (ix) FEATURE:                                                                     (A) NAME/KEY: Modified-sit - #e                                               (B) LOCATION: 4                                                     #/product= "OTHER"R INFORMATION:                                              #"aspartic acid is derivatized with                                                          amino-4-meth - #ylcoumarin"                                    -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:2:                                 - Tyr Val Ala Asp                                                             __________________________________________________________________________

We claim:
 1. A compound represented by the formula: ##STR175## wherein:m is 0, 1, or 2T is --CO₂ H, or any bioisosteric replacement for --CO₂ HR₃ is --CN, --CO--R₁₃, or ##STR176## R₅ is selected from the groupconsisting of: --H, --Ar₁, --CO--Ar₁, --SO₂ --Ar₁, --R₉, --CO--R₉,--CO--O--R₉, --SO₂ --R₉, ##STR177## each A is independently selectedfrom the group consisting of any α-amino acid; p is 2 or 3; each R₉ is aC₁₋₆ straight or branched alkyl group optionally singly or multiplysubstituted by --OH, --F, or ═O and optionally substituted with one Ar₁group, wherein the alkyl group is optionally unsaturated; each T₁ isindependently selected from the group consisting of: --CH═CH--, --O--,--S--, --SO--, --SO₂ --, --NR₁₀ --, --NR₁₀ --CO--, --CO--, --O--CO--,--CO--O--, --CO--NR₁₀ --, --O--CO--NR₁₀ --, --NR₁₀ --CO--O--, --NR₁₀--CO--NR₁₀ --, --SO₂ --NR₁₀ --, --NR₁₀ --SO₂ --, and --NR₁₀ --SO₂ --NR₁₀--; each R₁₀ is independently selected from the group consisting of --Hor a --C₁₋₆ straight or branched alkyl group; R₁₃ is independentlyselected from the group consisting of H, R₉, Ar₂, and --CH₂ --T₁ --R₉ ;each Ar₁ is a cyclic group independently selected from the setconsisting of an aryl group which contains 6, 10, 12, or 14 carbon atomsand between 1 and 3 rings, a cycloalkyl group which contains between 3and 15 carbon atoms and between 1 and 3 rings, said cycloalkyl groupbeing optionally benzofused, and a heterocycle group containing between5 and 15 ring atoms and between 1 and 3 rings, said heterocycle groupcontaining at least one heteroatom group selected from --O--, --S--,--SO--, --SO₂ --, ═N--, and --NH--, said heterocycle group optionallycontaining one or more double bonds, said heterocycle group optionallycomprising one or more aromatic rings, and said cyclic group optionallybeing singly or multiply substituted by --NH₂, --CO₂ H, --Cl, --F, --Br,--I, --NO₂, --CN, ═O, --OH, -perfluoro C₁₋₃ alkyl, ##STR178## or --Q₁ ;and each Ar₂ is independently selected from the following group, inwhich any ring may optionally be singly or multiply substituted by --Q₁and --Q₂ : ##STR179## X is N or CH; Y is O or S; each Q₁ isindependently selected from the group consisting of: --Ar₁ --O-Ar₁ --R₉,--T₁ --R₉, and --(CH₂)₁,2,3 --T₁ --R₉ ; each Q₂ is independentlyselected from the group consisting of --OH, --NH₂, --CO₂ H, --Cl, --F,--Br, --I, --NO₂, --CN, --CF₃, and ##STR180## provided that when --Ar₁is substituted with a Q₁ group which comprises one or more additional--Ar₁ groups, said additional --Ar₁ groups are not substituted with Q₁.2. The compound according to claim 1, selected from the group consistingof: ##STR181## .
 3. The compound according to claim 1, wherein each A isindependently selected from the group consisting of the α-aminoacids:alanine, histidine, lysine, phenylalanine, proline, tyrosine,valine, leucine, isoleucine, glutamine, methionine, homoproline,3-(2-thienyl) alanine, and 3-(3-thienyl) alanine.
 4. A pharmaceuticalcomposition comprising a compound according to any one of claims 1-3 inan amount effective for treating an autoimmune disease and apharmaceutically acceptable carrier.
 5. A pharmaceutical compositioncomprising a compound according to any one of claims 1-3 in an amounteffective for treating an inflammatory disease and a pharmaceuticallyacceptable carrier.
 6. A pharmaceutical composition comprising acompound according to any one of claims 1-3 in an amount effective fortreating a neurodegenerative disease and a pharmaceutically acceptablecarrier.
 7. The pharmaceutical composition according to claim 4, whereinthe inflammatory disease is septic shock, septicemia, or adultrespiratory distress syndrome.
 8. The pharmaceutical compositionaccording to claim 5, wherein the autoimmune disease is rheumatoidarthritis, systemic lupus erythematosus, scleroderma, chronicthyroiditis, Graves' disease, autoimmune gastritis, insulin-dependentdiabetes mellitus, autoimmune hemolytic anemia, autoimmune neutropenia,thrombocytopenia, chronic active hepatitis, myasthenia gravis ormultiple sclerosis.
 9. The pharmaceutical composition according to claim6, wherein the neurodegenerative disease is amyotrophic lateralsclerosis, Alzheimer's disease, Parkinson's disease, or primary lateralsclerosis.
 10. A pharmaceutical composition comprising a compoundaccording to any one of claims 1-3 in an amount effective for promotingwound healing and a pharmaceutically acceptable carrier.
 11. Apharmaceutical composition comprising a compound according to any one ofclaims 1-3 in an amount effective for treating infectious disease and apharmaceutically acceptable carrier.
 12. A method for treating a diseaseselected from autoimmune disease, inflammatory disease neurodegenerativedisease, or infectious disease in a patient comprising the step ofadministering to said patient a pharmaceutical composition according toany one of claims 4-6.
 13. A method for treating a disease selected fromseptic shock, septicemia, adult respiratory distress syndrome,rheumatoid arthritis, systemic lupus erythematosus, scleroderma, chronicthyroiditis, Graves' disease, autoimmune gastritis, insulin-dependentdiabetes mellitus, autoimmune hemolytic anemia, autoimmune neutropenia,thrombocytopenia, chronic active hepatitis, myasthenia gravis, multiplesclerosis, amyotrophic lateral sclerosis, Alzheimer's disease,Parkinson's disease, or primary lateral sclerosis in a patientcomprising the step of administering to said patient a pharmaceuticalcomposition according to any one of claims 7-9.
 14. A method forpromoting wound healing in a patient comprising the step ofadministering to said patient a pharmaceutical composition according toclaim 10.